Tuesday, July 22, 2014
Summer Assignment 7.22
Just one story this week; a longer piece on why we have blood types by one of my favorite science writers Carl Zimmer. You probably (hopefully) remember something about blood types from previous classes, and may even remember how to do the genetic crosses to figure them out. But have we ever thought about why we have different blood types? I know I never had until I read this article. Lots of interesting stuff in here, and overall it highlights a very important fact of evolution: If it exists, it most likely has an adaptive advantage.
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Why do we have blood types?
The topic that this article discusses is very interesting and unique. Most people know the different blood types that people have but not many people ask why all these types of blood exist and what they are for. Some questions that were discussed or that I thought about while reading the article is: Why don’t all humans share the same blood type? What characteristics does each blood type give to a person? How do different blood types affect illnesses and diseases in people?
The discovery of blood types happened more than a century ago and the succeeding discoveries and experiments of blood types and blood transfusions were very intriguing to me. One experiment that was interesting is when scientists, in the 1870’s thought that milk may have helped in transfusions. Once they tried this, scientists realized that this was not safe and it was deadly. I also found the blood type diet very interesting. Peter D’Adamo wrote the book called Eat Right 4 Your Blood Type. He believes that each blood type denotes which types of foods people should eat. Lastly, the Bombay Phenotype is also interesting because people with this rare blood type can only get blood from others with this same blood type, they can not get blood from people with blood type O, even though it is supposed to be the universal blood type.
Different blood types each have their advantage and disadvantages in illnesses and diseases. For example, blood type A has a higher risk of certain types of cancer, small pox, heart disease, etc. Blood type O has a higher chance of getting ulcers and rupturing the achilles tendon. I think that this is the reason for having different blood types. People need to be protected from certain viruses, bacteria and illnesses and different types of blood can protect people from different illnesses. If everyone had the same blood type, there would be some diseases that no one would be able to fight against.
Reason behind Existence of Blood Types Article:
The idea of evolution is quite a debated topic, by both scientists and creationists, and, especially the last few paragraphs were quite interesting to me due to the cellular level of evolution that the article claims to have created the diversity of blood types. The article is written fairly well, giving a backstory before using diagrams and wording to explain the point it is trying to get across. With the article’s explanation at the end being well written I do agree with the concept of hematological evolution to best fit survival and avoid the diseases that were most rampant at the time. Still, I am quite amazed that humans did not find and explore blood types until such a late time in the line of humanity, yet glad that we did so blood transfusion could be improved to save multiple lives. Overall, this article informed me of a great idea used in the medical field and the origin of the life-saving process.
-David Liu
I also never thought of why we have different blood types. It was interesting to see Peter D’Adamo's theory on where the different blood types might have originated from. I would love to know how he came to the conclusion that type O blood arose primarily in Africa from the hunter-gatherer ancestors and that type A blood came from the dawn of agriculture. What evidence did he collect/find that suggested that? As for the diet suggestion based on blood type, I think more experiments need to be conducted in order to strongly suggest that certain diets benefit certain blood type groups. For instance, Type A and Type B volunteers should be given vegetarian diets to see whether type A volunteers benefit more. The vegetarian diet seems like it would benefit almost anyone if that person eats the right foods. The meat-rich diet could also be somewhat beneficial to anyone if leaner meats and other nutritious foods are paired with it. The results of the experiment El-Sohemy and his colleagues conducted on the volunteers showed that the type A vegetarian diet seemed to reduce body mass index scores and lower blood pressure. I agree with El-Sohemy that the change in the volunteers had nothing to do with the blood type. Also I think that this blood type diet might have been more successful decades ago because I feel that people have changed so much over time. Our bodies probably handle food differently in this day and age where processed foods and high-sugar foods/beverages are typically consumed daily. This unhealthy lifestyle that people adapted has probably had an impact on the metabolism people have along with the power of their immune systems. Therefore I am not sure if this blood type diet Peter D’Adamo discusses could have significant impacts on people today. Also I'm assuming that since he hasn't published his decade long experiment with the blood type diet on women with cancer, he has not found that many successful cases. This article was very informative to me because although I knew that certain blood types can not mix with others, I did not know that mixing two non-compatible blood types would cause the blood to clump causing massive internal bleeding. Similarly to Carl Zimmer, I find blood types very mysterious as it is difficult to understand why there are different types with different structures.
-Richa
As I was reading, I was thinking: So where exactly is this article taking me? Wasn't this article about... blood? As I continued delving deeper and deeper into Zimmer's lengthy report, odd phrases such as "blood type diets" and "noroviruses" raced around in my mind. Thankfully, Zimmer's concluding thoughts relieved me just a bit. Zimmer said, "I realize that the reason for my blood type may, ultimately, have nothing to do with blood at all." and I say Amen to that. Yes, before reading this article, my knowledge of blood types was quite limited. Yes, I was enlightened with new information as I read. For instance, I learned about the past history of blood transfusions, Blundell, antigens, and the clumping of unlike red blood cell types. But the fact that scientists are still unsure about the origin and meaning of blood types is surprising. Since I have type A blood, does that truly mean that my ancestors were proto- farmers? My friend is type O, so will she one day die from ulcers and a ruptured Achilles tendon? It is frustrating that there is a dearth of evidence and support for such bold hypotheses. Fortunately, we are at least aware of the importance of different blood types for blood drives and transfusions because in the end, lives are saved. Technological advancements and the society's lexicon of knowledge never stop growing, so I am sure that a brilliant solution can one day shatter all ambiguity and mystery surrounding the topic of blood types.
Blood Types Article:
My blood type is B+, and I much like the author have always wondered the true significance of my blood type. I know I can't take the blood of someone with type A blood and et ceterea. However I found it extremely interesting how in the last few paragraphs the author used evolution as the cause for the blood types. To me it makes a plethora of sense, mostly because this trait was developed at least a few thousand years before the advent of humans, if not more. This would mean that every trait was used as a method for survival. Having blood types would make sense if like the author said, our ancestors were fighting pathogens however I personally think there could be more underlying causes. Although pathogens could possibly be the reason for the differing blood types, I simply don't think it is very plausible. This is because even if the pathogen, or the norovirus in the authors case, did kill off all the species except for the ones with the special blood types then the blood type AB would have been more prevalent. This is because, if I remember correctly blood types are genetically inherited though multiple alleles, and it is not simple mendelian dominance. Hence, when the species went through a massive die off and mating happened there would have had to be a decent amount of organisms with the AB blood type. This is because if a person with an A and B blood types mate, and assuming they are homozygous then there would be a fifty percent chance of the offspring having the AB blood type. This does not coincide with the information in the article which is saying that AB is a modern blend. That simply doesn't make sense because I am positive our ancestors did not mate solely with their own blood types.
Also another reason I don't think it plausible is because pathogens can evolve much faster than humans can, bacteria for example can reproduce through binary fission and can hence make millions of copies of themselves in a few hours. This is why they evolve much faster than humans do, and also why modern medicine such as penicillin is no longer effective on some bacteria. I would think that whatever the pathogen was, could have easily mutated a trait to circumvent the defense the blood types were providing.
Furthermore, even though I don't necessary completely agree with the authors theory, I do believe that evolution was the main cause of the differing blood types. I personally would like to think that a predator of some sort fed off of our blood. The predator could have been a poisonous blood drinker, maybe a distant ancestor of the mosquito or leech. Anyway I think that the blood types might have prevented the poison, but the blood drinking continued. This is more plausible because a predator like that would not have been able to evolve as quickly as a pathogen. Also the AB blood could be accounted for as well, if an antidote was eventually found for the poison. Even if our ancestors were primitive, I am fairly confident that a cure would be found although it may not have been very effective. However I believe there would be enough genetic diversity to allow for the AB blood to not be present. Therefore I have my own theories as to why we have blood types, but if anyone has something better I would gladly reconsider my theories.
Ashana P
I think that this article was extremely interesting and hit on a few key things that never occurred to me. Some of the things that they brought up in this article had to do with why there are different blood types among humans, if eating a specialized diet based on your blood type benefited you or not, the structure of our blood, and also the idea of blood transfusions. Blood transfusions were given a bad name for about 150 years, which surprised me since we now perform blood transfusions often to save lives. I understand why blood transfusions were given a bad name for so long since many deaths occurred due to them. Another topic that fascinated me was the idea of having a diet based on your blood type. The research that was performed by EL-Sohemy and his colleagues proved that there isn’t a relationship between your diet and your blood type. Having a vegetarian diet can benefit many people not just people with type A blood, and eating a diet rich in dairy products proved to have no benefits even though the diet was made for people with type B blood. I also learned that different houses could categorize the structure of our blood, which I was not aware of before. I never knew that type O blood only had the H antigen therefore causing it to be the universal blood type, but those with the Bombay phenotype can be killed by a transfusion with O blood. Those that have the Bombay phenotype can only accept blood from others with this type of blood. I was surprised to learn about new type of blood since I never knew that it even existed. Overall I think this article was very eye opening and taught me a lot more about the structure of our blood and the history behind blood transfusions. Lastly I was interested to know that different primates have blood types similar to ours and that Gorillas only have type B blood. This article was overall very fascinating.
Before reading this article, I had a very limited knowledge on the topic of blood types. I knew about the different types, the fact that it's an inherited trait, and that it's used for blood transfusions. However, I didn't know the history of it.
The first thing that I learned because of reading this article was that experiments of blood transfusions have been going on for centuries. I knew that the first couple wouldn't have been done with positive results but I was a bit shocked to find out that they had tried to put the blood of a calf into a human since even though they are both mammals, they have extremely differences which could potentially lead to disastrous results like it had in that case.
I was even more surprised to find out that there was an idea of having diets based on your blood type although it was disproved by EL-Sohemy. I didn't think that there really was a possibility it was true since my mom and I both have A+ and my dad and sister both have B+ blood types yet we're all fine eating the same food.
This article really taught me a lot about blood types, a topic that I had never bothered to dive deeper into before this moment.
I thought this article was very informative and intriguing. I was surprised to discover that the notion of blood transfusion was discovered in the 1600's; I always thought blood transfusion was a recent discovery. Furthermore, I was astounded to learn that blood transfusion was given a bad reputation for 150 years, whereas in modern era blood transfusion is used so commonly in surgery, accidents, et cetera. However, transfusion was given a bad name most likely due to poor technology and lack of a precedent which led to failures in experiments. Over time scientists learned more about blood transfusion and that humans should only get blood from certain other humans.
One part of this article that specifically fascinated me was learning about why only certain blood types can be transfused. For example, if A+ blood was mixed with type B blood the blood would clump together and disrupt circulation, cause bleeding, and possibly death. This depicts how important it is to receive the correct blood. In addition, I was puzzled by Landsteiner's question about why were there blood types. I think humans have blood types because when we were still evolving as humans our blood may have adopted to the climate and geography and as a result people of certain blood types may be less likely to get a certain type of disease.
Another fascinating topic was the Bombay phenotype. I find it extremely intriguing that some people may not have an ABO blood type. I have researched from Wikipedia that it is a very rare phenotype that is generally present in about 4 people per million. However in Mumbai (Bombay) locals can have occurrences as much as 1 in 10,000. This leads me to think that humans in the Mumbai region have a higher chance of being born with the Bombay phenotype because a unique disease or some unknown cause made the blood of the people in that region adapt to it. Overall the article was interesting and educated me about the significance of the blood types during transfusion.
The article surprised me, because I have barely ever given a thought to my own blood type. What first caught my attention was James Blundell’s reason for transfusions- though they had a bad reputation for 150 years, he still considered using them to save mothers during childbirth. Blundell’s crude name for interspecies transfusion- using “the blood of the brute”- aptly described the symptoms of the transfer of blood between human and animal. As was shown in the case of the transplant from the calf to the man, who very quickly showed symptoms of illness such as profuse sweating, vomiting, and passing “urine the color of chimney soot.” Though Blundell’s experiment (on the man who was bleeding to death) wasn’t a thorough success (two days after the transfusions the man felt “less fainty,” he soon died.), it still convinced him that blood transfusions would largely aid mankind in the pursuit of survival.
I was curious about the “various methods” Zimmerman mentioned following Blundell’s experiment; where did the idea to transfuse milk come from, and what else might they have tried? Very important was the fact that without Blundell’s assumption, scientists of the late 1800s wouldn’t have been able to discover the clumping of blood cells. Subsequently, Landsteiner would have been unable to map the clumping pattern of blood cells- which led to the discovery that only certain mixtures of blood would clump, and the types of blood were grouped into A, B, and C (O). It was also very interesting to see the correlation between the immune system of a person and their blood type (Blood type O only had H antigens, and A and B have both A and H antigens, but were structurally different. Peter D’Adamo’s later comments were fascinating- do our blood types have any relation with our dietary habits? Sadly, D’Adamo’s experimental trials have not been publicly published, hence Emmy De Buck’s comment on the lacking evidence supporting D’Adamo’s theory. Almost no amount of research on the general subject of Blood Types and Transfusions could be enough, there are links between blood types and so many things that it is hard to imagine that humans could ever hold all the answers.
Both blood types and the probability of getting certain diseases are strongly influenced by race. This supports the notion that the difference in blood types was an adaptive advantage to our ancestors. For example, Asians have a 25% of being B+ while Caucasians only have a 9% chance of the same blood type.In addition, Africans and Asians are much more likely to get diabetes than any other race. Both of these races also have a relatively high chance to get B positive blood type. However, I also noticed a general trend that some chances for blood types is not affected by race. Regardless of race, all humans are more likely to be O positive than B negative. This can be explained by natural selection of globalizing humans due to diseases. Over time, humans began to migrate from their own homes and live in other continents. While humans started to move, they also brought their diseases and spread them to other populations. A famous example of this is when European explorers brought smallpox in the Americas. Although exact numbers are not known, historians estimate that at least 70% of native deaths were due to smallpox. Another interesting fact is that 53% of Hispanics have O positive blood type. There is no strong evidence supporting a link between O positive blood type and smallpox, but this is due to the eradication of smallpox in 1980. However, according to the Smithsonian magazine, people with A blood type are inclined to be susceptible to smallpox. This could explain why only 29% of Hispanics have A positive. Nonetheless, I agree that the blood type immunity is ancient and are not the best type of immunity against diseases. As Ibshar said, pathogens are much more quicker in evolving than humans. Mitosis allows them to produce thousands of organisms in hours, and so natural selection and evolution will work at a higher pace than us. Human blood types will not be as effective against pathogens anymore and right now blood types for us are remnants of our ancestors.
URL for articles I used for research:
http://www.smithsonianmag.com/science-nature/the-mystery-of-human-blood-types-86993838/
http://www.yale.edu/ynhti/curriculum/units/2012/3/12.03.06.x.html
Why do we have blood types?
Blood transfusions are so potentially dangerous because blood types distinguish the line between seamless transfusions and deadly ones - whether one's immune system will react in a fury or if it will accept the blood without any trouble. The preciseness blood transfusion requires is rather scary, but it also speaks to the wonders of the body and how there is so much for us to discover about… ourselves. The importance of blood types cannot be understated.
It's upsetting how disastrous early experiments hindered the progress of future blood transfusions for many years; doctors were looking for a way to save their patients but feared killing them in the attempt. These were trying times, and James Blundell had crucial choices to make. He took many risks at the expense of desperate, dying patients' lives for the sake of a chance of helping them. What he did not know, however, was that humans should only get blood from certain other humans.
Noted for being the first to distinguish the main blood types, Karl Landsteiner led these efforts to new heights. Through observation of how red blood cells (both healthy and sick) stuck together, he worked through the combinations and mapped those that worked and those that didn't. He sorted the subjects into groups, which later became A, B, O, and additionally, the AB group. (Even later on, Levine discovered another way of categorizing blood, by whether it had the Rh blood factor or not, represented by a plus or minus sign.) Today, we have access to "safe, large-scale blood transfusions" thanks to Landsteiner’s basic and reliable blood type test by means of clumping.
Peter D’Adamo, author of Eat Right 4 Your Type, claimed that different blood types called for different, individualized lifestyles. He claimed that people of different blood types should eat different foods and exercise differently due to susceptibilities to different diseases, but many scientists in the field of blood types have rejected his claims regarding individualized dieting based on blood type. Emmy De Buck of the Belgian Red Cross-Flanders has spoken out on this subject, saying, “There is no direct evidence supporting the health effects of the ABO blood type diet.”
I believe that, most likely, the benefits provided by the ABO blood type diet aren't directly caused by a dieter's blood type. I agree with the writer of the article in that a healthy diet will yield positive results for anyone, no matter what their blood type is.
Links between blood types and diseases have a unsolved history, however, which trace back to theories regarding evolution. Do blood types really serve as an evolutionary advantage?
Nowadays, guesswork no longer has a place in the process of blood transfusion, and scientists are no longer alone in their endeavors. It's amazing that we have come thus far, but what's even more amazing is what's yet to be discovered.
This article on blood types was actually really intriguing. I always knew blood types existed, but did not really think about them in a biological sense until I studied how they are passed through sex-linked crosses. The article discussed how blood types could've originated due to evolution and different lifestyles of human beings during ancient times. This makes a lot of sense because from what I have learned and understand much of how our bodies work is because of evolution. So, it only makes sense that our blood would stick to the same principle by changing based on the living conditions of our ancestors. This can also be supported by the fact that each race is usually prone to have a certain blood type. Zimmer also discusses how different blood types have certain positives and negatives when it comes to diseases. For example, blood type A gives people a higher chance to have certain types of cancer. This supports the idea that blood types originated when the first groups of people settled across the globe because each blood type can show how that person's body evolved to protect itself from the biggest risks in their certain environment. Even though the blood type doesn't directly link to the diseases that that person is prone and not prone to, I still think that the blood type can tell where the person originated from and how their body works to see what diseases they are highly susceptible to and not. Blood types also relate to the principle of natural selection because during the article, it discussed how certain blood types became very scarce and soon nonexistent because the organisms with that blood type did not survive to reproduce and pass on their DNA. The only questions I have left are why is the O blood so versatile and will there ever be a universal blood type as time goes on and all different races begin reproducing and living with one another? National Geographic says by 2050 the average person will be of mixed race, so does that mean that overtime their blood types could meld into a mixed universal one if that is even possible over centuries or even millenniums. Overall, this article on blood types I thought was very well written and well thought out and brought up some very valid points on the ideas of the origins and importance of the different blood types.
Prior to reading this article, the cause of having different blood types had never crossed my mind. Reading the title of this article immediately gained my curiosity as it had brought me back to 9th grade biology. I had seldom knowledge, from what i remember, of the different blood types, but it was enough to help me understand this article without using an outside source. Right in the beginning, it explained why blood transfusions were looked down upon for nearly 150 years. In today's world, it sounds ridiculous that Renaissance doctors would even try a transfusion with another animal, but back then they had little knowledge of blood. Moving forward to when Blundell thought that blood shouldn't be shared amongst species, but amongst each other. To me, this sounds like common sense but at the time, it was groundbreaking. It surprised me that later on, the scientists would neglect the one possibility would be that certain humans can attain blood from only certain humans. I believe that they were too quick when they determined that the clumping was caused by diseased blood and wouldn't study further.
Also, the feature of why only certain blood types can mix (The houses and the H antigens) led to an easy and effective understanding of how blood mixing works.
D'Adamo's comments were rather peculiar, but sparked an interest in me. It gave me the thought that "maybe if I change my diet accordingly, I can have a healthier lifestyle." This idea went away as I read on to discover that there was really no scientific evidence to support it and the experiment results had yet to be returned. It is a fascinating idea but it will take a lifetime to truly figure out if this is true.
Normally i resent reading articles as lengthy as this, but this caught my interest and i enjoyed reading till the end. It makes me wonder if we will ever truly know the origins of different blood types and how they formed, where they came from, and the benefits of having a certain blood.
This article was intriguing as it was frightening. On one hand, the article was intriguing by it giving me information that I never knew on the different types and also giving me reasons on the purpose of the various blood types. I never knew that there was a structural difference between blood types, and that one blood type had two stories, another had one, and another none. In addition to this, it never occurred to me that the structure of blood would determine whether the blood would clot or not when mixed. It also never crossed my mind that blood types would have been regional and that each were susceptible to and protected against certain diseases. The good thing is that we have learned about this now and many people's lives have been saved because of it. The only thing I disagree with in this article is when it says that blood types determine how a person should eat (Blood Type Diet). I believe that everyone can enjoy the benefits of a vegetarian diet, no matter what blood type they are. A disappointing thing about this is the time at which we discovered this. The late time of discovery does make sense to me since the methods used for research in the early stages of this topic was all by trial and error. However, if scientists would have discovered this sooner, many more lives could have been saved. Overall, this well - written article left me both curious and puzzled about blood types.
-Kausthub Vedantham
The misconceptions of science in history have always interested and sometimes amused me. I found it quite intriguing that Renaissance doctors were thinking of blood transfusions in the 1600s. Although they didn't have enough information to be successful, the fact that they attempted the procedure with calf's blood was surprising. However I imagine they believed that all blood was the same and since they didn't really have laws and codes limiting their experiments there was no reason for them not to...say-transfuse calf's blood into an insane man.
On the subject of actual blood types that were discovered later and why they evolved, it makes sense to me that they evolved to fight certain diseases. I wonder if there is an enzyme or different linking factor between the diseases that different blood types are more at risk for or better defended against. I highly doubt that they evolved randomly, that wouldn't make sense, there must be some linking factor.
Anyway, back to the original question- why do we have blood types? I'm not going to say I know for sure, but I think what Carl Zimmerman was alluding to with different blood types giving different groups within a species certain advantages and disadvantages helps the species as a whole and definitely makes sense in terms of evolutionary advantages.
This fascinating article regarding blood types caused many questions to arise in my head. At the same time, it nurtured my mind with a variety of new information.I was surprised to read that the blood types may have existed since 20 million years ago. In fact, blood types may be even older but our technology is not able to harness that information yet. But the main question that was fluttering around the author’s and my mind was “why do we have different blood types in the first place”? The author mentions that the result of mixing two different blood types together with the exception of type O blood would result in a clot because the blood will clump together. This is because type O is the universal donor, which is contained in every type of blood except the Bombay Phenotype. However, if the same blood type is mixed, the blood would continue to stay in a liquid form. This fact was perceived after many years of medical research and transfusion. For instance, James Blundell was an earlier scientist who tried transfusions. One of his patients needed immediate blood and was supplied with a different type of blood. However, he lived for two more days then died because of blood clots. This occurred because a different type of blood was transfused into the man. In addition, a French Scientist transfused calf’s blood into a man, which resulted in the patient’s death. Although the patient died and other transfusion deaths occurred, Blundell received the notion that blood cannot be transfused among the different species. After reading this I was shocked because I thought it was ridiculous to transfuse blood from another species and I felt nostalgic that the patient lost his life because of a vacuous hypothesis. However, I was glad at the same time because without this and many earlier experiments, Blundell would not of had the notion that blood cant be transfused among different species. Moving on, the author mentions that the different types of blood are more immune to different blood related diseases. Further research is required to confirm this theory. The article mentions that some Noroviruses have the same probability of attacking any type blood. In addition, this was the first time I was hearing about the “ Bombay Phenotype” and I was shocked to learn that this type of blood doesn’t have either type A, B or O in the bloodstream. The article mentions that there is no additional threat posed towards these humans for having such a rare blood type. I was especially surprised as the article progressed because it mentioned the theories of a man named Peter D’Adamo in his book “ Eat Right 4 your Type”. The article mentions that humans should eat a wholesome diet according to their blood type. This increases the metabolism as well as helps to keep a sparse waistline. For instance, people with blood type A were recommended to eat veggies, while people with type O were recommended to eat meat rich diets. However, many people argued that this theory is false because his bold statements were not backed up with scientific endorsements. After conducting an experiment to prove his theory the results show that some cases were correct. However, the article additionally mentions that the diet has no health effects because our blood type does not have any connection with our diets. Moving on, I found it interesting when the author wrote that our blood might of evolved because the pathogens became adapted and exploit against different blood antigens. The pathogens matched with the most common blood type would of live longer. Therefore, they would commence killing off their host causing rarer blood types to live because there are less pathogens attacking this blood type. This is probably how our blood types have lived for millions of years. All in all this article informed myself plenty of blood related information.
Why do we have blood types?:
According to this article, the interest in blood types began in the early 1600 when a few doctors tested the idea of mixing blood with disastrous results and it has fascinated the medical community for centuries. In 1900s the Austrian physician Karl Landsteiner first discovered blood types, winning the Nobel Prize in Physiology or Medicine for his research in 1930. Although doctors discovered that blood transfusions can save lives and blood types differ from each other and that humans should only get blood from certain other humans, we still do not know enough to determine their function in the human body.
It really fascinated me to read how little we know about our blood type even today despite all the progress made in the field of medicine. “Almost a hundred years after the Nobel Prize was awarded for this discovery, we still don’t know exactly what they’re for.” The article made me wonder why people do not have the same universal blood type. Where did these different types of blood originate? And could blood be another sign of evolution? These questions need to be answered because they may be a key to the survival of the human race.
Evolution is the result of mutations, so in my opinion, it makes logical sense that blood types are probably a result of mutation as well. It has been established that blood types are very old and together with the monkeys, we inherited these from a common ancestor almost 20 million years ago. Since mutations are in charge of shutting down one blood type or another and altering genes, it probably makes sense to assume that there were many more blood types back then than the few that exist today. And over time blood types evolved to the current A, B and O in humans.
It is interesting to see how blood types also dominate certain races. For example, 40% of Caucasians have blood type A while only 27% of Asians do. So there might even be a correlation between a person’s blood type, their race and the region their ancestors originated.
According to Peter D’Adamo, we must eat according to our blood type, in order to harmonize with our evolutionary heritage. He claims that we should eat based on our blood type to reduce infections, lose weight, fight cancer and diabetes, and slow the ageing process. I disagree with his claim because in my opinion two people may respond very differently to the same diet based on their genes. Moreover after eighteen years of research, D’Adamo is unable to publish the data from his trial, which leads me to believe that his hypothesis might be a potentially good idea, but there isn’t any reliable data to prove that it is true. “None of the stuff in the book is backed by science.”
While I was reading this article something occurred to me. If the process of blood transfusion has existed since the 1600s, why did it until the 1900s for scientists to realize blood types could not be mixed. As I continued reading, I got my answer. Blood transfusion did not have great stature in scientific world for so many years, people never bothered to experiment with it too much because the outcome could have been very dangerous. Karl Landsteiner's simple discovery set in motion more discoveries to come.
What I found most interesting was the existence of Bombay blood. It is so fascinating how most of the people in the world have ABO blood types while these few people have something completely different. Thought it is very unique position for someone to be in it is also very dangerous because of the fact that it is so rare, and how O blood cannot be used for a substitute.
In the beginning of the article Zimmer states that when he was younger he assumed that his A+ blood type made him stronger but soon discovered that it was not the case. I will admit that a few years ago that I thought I was special because I had B- blood and the doctor told me it was rare. As I got older I also realized that it was not true. After reading about the Blood Type Diet, I was a little intrigued. Is it really possible to be at your best health and strongest if you follow this diet? Could it actually work? As I was thinking about this strange idea it occurred to me that it cannot possibly be true because my family members all have different blood types yet they do not eat like the diet stated yet they are perfectly healthy. So, like the other scientists in this article, the Blood Type Diet was blown way out of proportion and in many ways is simply wrong.
I found this article very informative and when it finally comes time to donate blood I will know more than enough about blood types.
Before reading this article, I never gave much thought to the idea of blood types and blood transfusions. I, as well as many others, never questioned the existence of blood types and just assumed they were a part of life. It was interesting reading about past clinical trials and previous failed blood transfusions. Blood types had been relevant for centuries before anyone thought of the idea of blood transfusions and many questioned how they came about. Peter D'Amado's theory states that human diet at the time determines one's blood type. He theorized that people with blood type A usually are vegetarians while people with type O are from Africa and are hunters that avoid dairy and grains. Blood types have been a mystery to most before this article and the metaphor to a multilayer house is a good way to present the different types. Every type of blood is different and distinguishing each type can be difficult. It has taken many years to finally figure out the correct process to transfuse blood from one person to another and scientists are furthering their research in order to better the processs.
Why do we have blood types?
It is interesting how doctors thought of transfusing blood into patients in order to save their lives. Even though it didn’t work in most cases, doctors kept researching. Through trial and error, new observations and discoveries were made. The first huge discovery about blood types was in 1900. Karl Landsteiner, an Austrian physician, discovered blood types, winning the Nobel Prize in Physiology or Medicine. An amusing point in this article was made by Ajit Varki, a biologist at the University of California. He said, “Isn’t it amazing? Almost a hundred years after the Nobel Prize was awarded for this discovery, we still don’t know exactly what they’re for (blood types.)” As humans studying the field of science, we have matured and learned a lot. There is still more to be studied and learned. More time invested into research means more fruitful results and understanding.
Examples of the growth of knowledge through research were the discoveries of blood cells clumping. Landsteiner set out to map the clumping pattern of blood from healthy members of his lab, including himself. He found that the clumping only occurred if he mixed certain people’s blood together. He came to a conclusion of three blood groups. These were A, B, and C (later named O.) A few years later, other researchers discovered the AB blood group. Later on in the middle of the 20th century, American researcher Philip Levine discovered one more way to categorize blood. This way was based on whether the blood had Rh blood factor. (A plus or minus sign at the end of the blood group letters indicates whether a person has the factor or not.) These discoveries were the building blocks of the true understanding of blood. Based on these breakthroughs in science, transfusion success rates would increase, as more lives would be saved.
Why do we have blood types?
Just like the author, my blood type is A+, and the funny thing is that in the third grade when I was told that I had an A+ blood type, I thought it was because of my grades in school. Of course when I got older I knew that was not the reason why my blood type was an A+, but I wondered what it meant to have that blood type. I am not happy to hear though that the blood type of A puts me at a higher risk of cancer.
The fact that blood types are related to evolution is very interesting. It seems quite plausible because evolution has changed many things about different people from different regions. Although, I don’t think that blood types should have anything to do with food. My A+ blood type arose at the dawn of agriculture, so my diet so include a lot vegetables, but I absolutely love meat. I also need a lot of meat for its protein because I’ve changed my diet to maintain a six-pack, but I have always loved meat since I was a small child. Perhaps there is another factor in blood types that affects diet, which has not been found. After all, this research is very new and I surprised that it took so long to investigate this interesting topic.
Before reading this article, I didn't have much knowledge on blood types, but by the end of the article I learned a lot of new information. I found it interesting that many people had to die before they realized why the transfusions would only work for some people while not others. I was stunned to find out that for 150 years transfusions were given a bad reputation, but it is now understandable. Since, doctors didn't know that there were different types of blood types when they performed this procedure of transfusion; it ended up working only for certain people. A scientist known as Karl Landsteiner then figured out why the transfusions were not effective; the blood would clump up in certain people’s bodies and these clumps could cause bleeding. Once he tested people’s bloods together he was able to establish that people had different types of blood, and came to the realization that A and B blood types would only be used for people of those of the same blood type, yet blood type O was a universal donor. I thought it was interesting that he actually had to test the different blood types, and was able to see that it would either clump up or remain liquid. Even though I found the process of which he came to the discovery interesting, I was shocked to find out that it took scientist such a long time to finally figure out why transfusion was only working for some humans.
Throughout the whole article the one thing that stuck out to me the most was the blood type diets. Peter D’Adamo was the man who came up with blood type diets and wrote a book about it known as Eat Right 4 Your Blood Type. Ahmed El-Sohemy, a nutritional scientist got 1,500 volunteers to conduct a study where they would watch what types of foods people of a certain blood type would eat. Each blood type would get a specific diet and by the end of the study, El-Sohemy found out that these diets did help people, but not for the reason people thought. It stated in the article that a diet would help anyone, so it didn't have anything to do with a person’s blood type, just the fact that it was a diet. Even though the diets didn’t help for a specific blood type, I started to ponder on the thought that if these diets did help, would people who were only on these diets be valuable clients for donating their blood. Would scientist then only want people who were on these diets to donate blood? If these diets did work, maybe they would have caused more damage than any actual help. The blood type diets weren't efficient yet were still fascinating to even think there could have been such a possibility. This article allowed me to open my eyes and learn much more about blood types.
I came into this article with a very limited amount of knowledge about blood types, and more importantly, how they came to be. Everything I knew was obtained from seeing the aftereffects of tragedies, telling donors they needed more type A blood or type B blood. From this, I knew there were different blood types and that they couldn’t be mixed, but this longer and more in depth article gave me a greater understanding of this topic.
Throughout the article, I found myself intrigued as I pored over each word that the author had written. I was surprised to see the history of how blood transfusion became a procedure today, especially the fact that for 150 years, it had a bad reputation. I felt this way due to the fact that we use it so commonly now after car accidents, during surgeries, and other things along that line. One part of the article that had me leaning in closer to my laptop, as if by moving closer to the words would get me more involved in them, was when the author was explaining why only some blood types could be transfused. I had previously asked my parents about different blood types and why they couldn’t be mixed, and now I understand that the clumping of the red blood cells are the reason they can’t be mixed. For example, if type B blood was transfused into a person with type A blood, serious complications and even death could occur due to the clumping of the cells. By understanding this, all the dots in my mind connected to everything I ever heard about blood types.
Although I found many points in the article interesting, one that amused me as well as intrigued me was the “Eat Right 4 Your Type” topic, which was brought up by a man named Peter D’Adamo. I found it very thought provoking to see how this man thought about how the origins of blood types could tie into other aspects of our lives, specifically, into how it can either make or break a type of diet. He believed that type O blood came from our hunter-gatherer ancestors in Africa, type A came from the dawn of agriculture, type B developed between 10,000 and 15,000 years ago in the Himalayan highlands, and type AB was a modern blending of types A and B. A type O diet was meant to be meat rich and made to avoid grains and dairy. A type A diet was one strictly vegetarian, and a type B diet was dairy based. Despite how quickly the public ate it up, eager to believe anything when it came to weight loss, the Red Cross in Belgium was quick to disprove D’Adamo’s theories about dieting by blood type by running experiments that followed the diets. However, D’Adamo’s beliefs on how the origins of blood types effect other things helped open the doors to different schools of theories and thought on the topic, which are still being researched today.
Overall, I found this article informative. I find that blood types are one of the more interesting parts of biology. Previously, I knew only the basics of blood types. I knew that blood type O was the universal doner and blood type AB was the universal receiver. After reading this article, I learned many things.
First off, I learned about what happens during a blood transfusion and how it can go wrong. Before, I knew that a transfusion was a way to transfer blood from one person to another in the case of blood loss. Blood types have different antigens. Type A has A antigens and type B has B antigens. Whereas type AB has both antigens and type O has neither. If a person receives blood with the opposite antigens, they will die. This because the immune system will not recognize it. The blood will then clump up. In contrast if they receive blood with the same antigens, they will live. The blood will remain a liquid instead of clumping up.
I also thought is article has many interesting information. The fact I found most interesting was that about the Bombay phenotype.This was discovered in 1952. The red blood cells lack all of the ABO blood group antigens. The individauls can not make an A or B antigen. The people with this can not receive transfusions from any other blood types than other people with the same type. I found this information really interesting because I never knew about it although it's existed for more than 60 decades.
I was also interested to learn how blood transfusions started. Many Renaissance doctors were the first to try this. At first, they used blood from other animals. This resulted in death. Things like this gave blood transfusions a terrible reputation for 150 years. I find it interesting how people were not willing to try anything for that long. James Blundell, a British physician was one of the first to try using human blood. Out of 10 people, 4 survived. The puzzle was almost solved. All that was needed was the discovery of different blood types. Karl Landsteiner a man who was intrigued by blood. By performing experiments, he categorized blood into three groups including Types A, B, and O. All he didn't know was the difference between them. Future scientists discovered the antigens in the blood types. Thus, people discovered how to accurately perform blood transfusions. I still find it interesting how long it took.
Overall this article was very fascinating. I enjoyed discovering new information about blood that I never knew. This will definitely be one of the topics I will be looking forward to next year.
This article by Carl Zimmer was intriguing and fascinating. Most people today don’t really understand the significance of blood type and honestly I was one of them. After reading this article I found out how important blood types were and how it affected your body. Before reading this article I thought to myself why was blood type so important? Who and why did someone classify blood types? Well, as these thoughts were cruising through my head, I read through the article. Over a century ago an Austrian doctor named Karl Landsteiner had discovered blood types. Winning The Noble prize, Landsteiner went to be the first doctor to separate blood types into A, B, and C later known as O. But of course not doing it alone a British doctor named James Blundell first tried to transfuse blood before Landsteiner. James Blundell results of transfusing blood came to a halt when six out of his 10 patients had died from blood transfusing. During the 1800 scientist mixed blood from different people. They observed that occasionally the red blood cells stuck together. Scientist assumed this happened because they were generally using sick patients’ blood, so scientist ignored the clumping. However, one scientist saw this as an issue and that was Karl Landsteiner. Karl Landsteiner tracked the clumping patterns and collected blood from his colleagues and himself. He noticed that the clumping of blood came when he mixed certain peoples blood. Landsteiner came up with arbitrary names for these as stated before they were Types A, B, and C (c later became known a O). He also found out that Type A bloods can only go with Type A patients, Type B bloods can only go with type B patients, and Type C (O) can go to type A, B, and C. What I found fascinating was that each blood type had its own structure. For example Type A was described as a house with two floors. The first floor was called H antigen and the second floor was called A antigen. Type B was also described as a house with two floors but what was different was that the second floor was shaped differently. Lastly Type C (O) built a single-storey house they only build the H antigen as described by Zimmer. To conclude, I leant a lot of new information on blood types. Like Carl Zimmer I was fascinated by the importance of blood types and how it can help peoples health.
Both blood types and the probability of getting certain diseases are strongly influenced by race. This supports the notion that the difference in blood types was an adaptive advantage to our ancestors. For example, Asians have a 25% of being B+ while Caucasians only have a 9% chance of the same blood type. However, I also noticed a general trend that increasing chances for blood types is not affected by race. Regardless of race, all humans are more likely to be O positive than B negative. This can be explained by natural selection of humans due to diseases. Over time, humans began to migrate from their own homes and live in other continents. While humans started to globalizing, they also brought their diseases and spread to other populations. A famous example of this is when European explorers brought smallpox in the Americas. Although exact numbers are not known, historians estimate that at least 60% of native deaths were due to smallpox. Another interesting fact is that 53% of Hispanics have O positive blood type. There is no strong evidence supporting a link between O positive blood type and smallpox, but this is due to the eradication of smallpox in 1980. However, according to the Smithsonian magazine, people with A blood type are inclined to be susceptible to smallpox. This could explain why only 29% of Hispanics have A positive. Nonetheless, I agree that the blood types are ancient and are not the best type of immunity against diseases.
http://www.smithsonianmag.com/science-nature/the-mystery-of-human-blood-types-86993838/
In the beginning of this article, I was looking forward to reading or finding the answer as to why blood types exist. However, as I got deeper into reading, I gained a lot of knowledge on how blood transfusions lead to the discovery of blood types. The experimentation of blood transfusions which were conducted by many scientists failed miserably. Blood transfusions were looked upon as a deleterious method to cure someone. However one scientist – James Blundell didn’t give up. He figured out that blood transfusions between different species was not going to work. He realized this key fact and even stated that “the different kinds of blood differ very importantly from each other”. He then proceeded onto human transfusions which did not work, however he had some conviction that this method was the solution.
During the 1800s when scientist mixed blood in test tubes, the blood would often clump together. However scientists never bothered to investigate this occurrence since they usually took the blood from sick patients and speculated that this was the reason why the clumping occurred. However, when Landsteiner finally questioned this and decided to experiment, the powerful discovery of blood types was made. This then lead to the segregation of the different blood type groups ( A, B, AB,O)
One thing that really captured my attention was how our blood types today, survived all these years. Scientists traced back our blood types to millions of years ago. Our ancestors were vulnerable to many different types of pathogens. The blood type and their antigens which were most prominent during that time were infected the most and this normally resulted in the “killing of the host” who had been infected. That is why the more rare blood types seize to exist till date. So technically that means that our blood types today were considered to be the rare ones millions of years ago.
Another discovery which was made was that diseases and blood types have linkage. A person may be prone to certain diseases depending on the type of blood they have. This can be very helpful to people today since it can be used as a proactive method to take precaution against these diseases ( since they are more prone to them) . Even though we have discovered the benefits of blood types and its helped the medical field advance in helping humans, not knowing the purpose of them is still a major setback. It is a mystery yet to be explained which im sure holds many more possibilities and advancements towards the science and medical field.
I do not know what my blood type is, but after reading this article I thought to myself that it would be a good idea if I found out. Something that occurred to me after reading this article is that our generation is the pioneer in research of the blood. The abundance of unanswered questions and bizarre theories developed remind me of the article about life on Europa from last week. This article brought up so many interesting facts about blood like the different types and how it relates to the different people around the world. Something new I learned today was how the Types A,B and O differed and why O can be used for transfusion with the other two. I found D'Adamo's book very absorbing with the theory he wrote about and the evidence he used to support it. I was somewhat disappointed when I later learned about the experiment done by Red Cross in Belgium to see his theories were actually true. Unfortunately they were proven false but the author argues the science is right. The rare Bombay phenotype gene of the blood is fascinating and scary at the same time because if a person had this gene they would not be able to receive blood from anyone except another person with this unique gene. All these unanswered questions about the origin of the blood types and what purpose it serves bewilder me. Knowing some of the answers to these questions in the future will help us understand blood types better but will open doors of more questions that will yet to be answered.
Until I read this article about why we have different blood types, I never questioned this fact, only accepted it. As I progressed further into the article though, I immediately became fascinated by this topic and the reasons behind it. I found the theory about how blood types developed in different groups of our ancestors to be very interesting because this would explain why various races have a different percentage of people with each blood type. According to the naturopath, Peter D’Adamo, we must eat the foods corresponding to our evolutionary heritage in order to remain healthy. Foods that aren’t suited to a specific blood type can supposedly contain antigens that are harmful to an individual’s well being. This theory led to the introduction of the Blood Type Diet which is surrounded by much controversy though. In some cases, this diet showed no changes in health but in others it showed improvement which may or may not actually be related to blood types. There is still much investigation that is required in order to determine if this diet really works but the evidence brings me to question whether the Blood Type Diet is truly effective or if it is just a well employed marketing tactic to convince people to purchase various diet supplements tailored to their blood type. Something else that caught my attention was the ABO gene. I found it intriguing how it developed due to mutations and how even today, we still do not understand the purpose of this gene. There are some people with no ABO blood type at all which is shown in the shocking discovery of the Bombay phenotype. The rare and peculiar Bombay phenotype manages to further confuse scientists when it comes to the topic of blood types because these people can only receive blood from people with the same condition. Not even O, the universal blood type will suffice, which causes a problem in case someone with this phenotype is badly injured. The conclusion that I came to after reading this article was that the purpose of having different blood types is to protect us from different diseases. Each blood type is prone to, or has a higher risk of obtaining certain illnesses such as cancer. If we all had the same blood type, we would all end up with the same diseases that we could not escape, so in a way, having different blood types is something that makes our species stronger. Possessing a rare blood type can also help an organism survive as seen in our primate ancestors who were able to remain safe from countless pathogens because these different viruses and bacteria would have adapted to benefit from the most common blood type, leaving the others alone. Having a certain blood type can be both a blessing and a burden, but it was a necessary evolutionary process that may have even more biological benefits to be discovered.
Growing up I have also wondered why people had distinguishing blood types. I think that finding what makes our blood a certain type is essential for the article does provoke the certain advantages and disadvantages of certain types. For instance, individuals with type A, as mentioned, are prone to getting a diagnoses for pancreatic cancer. Knowing that my blood type is O positive, I have also learned from Zimmer's findings that I am "... more likely to get ulcers and ruptured Achilles tendons." However, what I find interesting is how Zimmer mentions D'amado's take on how people have optimal health based on specific diets to follow, depending what the blood type is. His hypothesis happens to be similar to the diets of our ancestors back in the day that came from the Himalayan High Lands, the African areas, and agricultural lands. However finding it that El-Sohemy found no fruitful scientific evidence supporting that the diet has something to do with the blood type, then what would have caused the participants in his experiment to experience positive results? Is there a possibility that these findings may have been caused by a placebo effect? The reason as to why I think this may be a possibility is because of the mindset of the volunteers before they did as told by El-Sohemy and his colleagues. Also, this could be the reason as to why D'amado argues against his critic stating how "There is good science behind the blood type diets, just like there was good science behind Einstein's mathematical [sic] calculations that led to the Theory of Relativity." Lastly, another intriguing fact that Zimmer has written was the Bombay Phenotype; since the roof of their red blood cells is an empty lot, they can't get a blood transfusion from anyone except other Bombay Phenotypes.
The history of blood is very interesting. From the point when people realized the life-giving properties of blood, the liquid was experimented with. In the early days, people attempted to cure maladies with leeches and bloodletting. This slowly evolved into various experiments with transfusions, which eventually resulted in the modern-day understanding of blood, transfusions, and the medical conditions that can arise because of blood.
A major innovation in the field of hematology was the discovery of blood types. For centuries prior to Landsteiner’s ABC (later changed to ABO) categorization (and later, Levine’s contribution of the Rh factor), scientists observed things about the blood, such as the way it sometimes clumped when two people’s blood was mixed. This discovery changed the process of blood transfusions. Before Landsteiner’s categorization of blood types, several different attempts were made to transfer blood blindly. Starting with failed interspecies and milk transfusions, scientists figured out that transfusions should be done between humans. Even with that information, scientists lacked the crucial understanding of blood types, and human blood transfusions resulted in a 40% success rate (for physician James Blundell).
However, the crucial findings in 1900 increased the success rates of transfusions considerably. Learning about transfusions and their history raised a number of questions in my mind. In today’s world, things we used to think were impossible have become possible, especially in the medical field. Previously, people refrained from mixing blood types because of the clotting: would it be possible to mix non-compatible blood types and inhibit the clots from forming with modern day medicines such as anticoagulants? With interspecies transfusions, people once used organisms such as cows, but it has been found that some primate species have variants of human blood types: could humans accept transfusions of similar primate blood? Interspecies transfusions also raised another question in my mind: why is it that human bodies can tolerate interspecies transplants (pig organs are used for interspecies transplants and other procedures) but not blood?
While thinking about the possible link between blood types and evolution, one may suppose that it is very possible that blood type diversity may have been a contributing factor in evolution around the world. It has been shown that blood types have a natural protection and vulnerability to certain ailments. Could it be possible that these tendencies were shaped by environmental factors over generations? I believe that blood types possibly have some type of evolutionary advantage; in the past, most vestigial structures are eliminated in the process of evolution. Reading about the possible reasons blood types exist raised a few questions in my mind. Is there anything to learn from studying blood types in relation to the diseases they are prone to? Is it possible to artificially synthesize blood to help those in need (and to create it for those with rare types, like the Bombay phenotypes)? Is it possible to make all blood universally interchangeable (as opposed to within the specific blood type)? Why are there rare blood types? It seems certain to me that blood, the elixir of life, holds many more mysteries that will puzzle scientists.
The most mind-blowing aspect of the whole article to me was the way these scientists were able to find that there are different types of blood. Many people would not even think twice about the way blood is grouped and distinguished; to them a blood type is just another category. It took a couple of centuries for scientists to find a solution on how to safely transfer blood. The way that Karl Landsteiner looked at the issue with a different thought process led to a major breakthrough in the process of saving many lives.
Another interesting idea introduced in this article was the one about eating based on what blood type a person has. I did not think that one’s diet had any correlation to the type of blood in their body; it just seems unnecessary because in today’s society nobody knows of the advantages and disadvantages of limiting their diet to the correlation with their blood type.
The chances of someone living with the Bombay phenotype are much more limited than another person with A, B, O or AB blood because having the Bombay phenotype is so rare. Anyone in that situation would have a lot of trouble finding eligible donors. If those with the Bombay phenotype only have “an empty lot,” then what do their blood cells look like? There has to be some kind of “house,” or is it actually just a blood group without any antigens?
Lastly, norovirus struck me as really random. Why does the norovirus correspond with the blood type if it does not even touch the blood cells? The article says that there are other cells to produce the antigens but how do those cells differ from the antigen-producing cells in other types of blood? Since the cells produce different types of antigens then it is understandable but the whole non-correlation just seems really strange.
From studying blood types in brief last year in biology, the only things I really associated blood types with were Punnett squares and blood transfusions. It was very interesting to read how blood types connect with more than just your blood. From specialized diets based on when your blood type first came about, to risks for certain diseases, your blood type can certainly influence your life more than you think. The article made me think deeper about blood types than I have thought about them in the past. It was also intriguing to learn about how early scientists experimented with blood types. Simple facts that we take for granted today, like how certain blood transfusions are successful, and how others cause blood clots have resulted from extensive research I never had known about.
Prior to reading this article, I had very limited knowledge regarding the different blood types. All I remembered was the basic information I had learned in my freshman biology class. It amazes me to see how far medical science has advanced in today's society. We wouldn't have the vast array of information we have today pertaining to blood types if it weren't for the efforts put in by doctors and scientists starting from the time of the renaissance. Blood transfusions save countless number of lives everyday and it’s shocking to me that they were in fact looked down upon for 150 years! While reading this article, I was fascinated by Karl Landsteiner's ability to sort out and distinguish the different kinds of blood based on the clumping of the red blood cells. His research led to the discovery of blood types A, B and O. Some questions that I am still intrigued by are, why is it that type O can donate blood to any type but cannot receive blood from all types and what other factors besides heredity play a role in determining a person's blood type? The one aspect from this article that I'm not sure if I agree with is the blood type diets. I agree with Emmy De Buck of the Belgian Red Cross who said, "There is no direct evidence supporting the health effects of the ABO blood type diet." Just like Ahmed El-Sohmey, I do not believe that blood type has anything to do with a diet's success. A person with blood type O can benefit just as much by having a vegetarian diet as a person with blood type A. Nevertheless, El-Sohemy did find that these diets were beneficial to many people, but the success was not because of blood type. After reading this article, I have gained a much better understanding on the different blood types and where they originated from. I am now intrigued to go find out what my blood type is as well!
Blood type is like arranging a puzzle together, it has to fit perfectly or else clumps will start forming. This could potentially kill many people. Before reading this article I knew that we could mix certain blood types together, but what i didn't know was what happens. Each blood type has its own build up of molecules for example A blood type has H antigen and A antigen which can not mix with blood type because its "a antigen" is shaped differently. On the other hand, people who have blood type O, only H antigen which allows them to donate blood to any type.
Furthermore, in the article I read that D' Adamo wrote a book about Eat Right For Your Type. It fascinated me that each blood type originated from a certain part of the world for instance, type O developed from hunters in Africa. He also mentions that people should have a certain diet that benefits their blood type. For example, type O should only eat meat. In this situation, I do not agree with D' Adamo because a human being no only needs protein, but also needs carbohydrates, different types sugar, dairy and many other aspects that benefits to humans. So, a person should not have a certain diet based on their blood type.
Ultimately, I learned a lot by reading this article. I glad that I am a universal donor and I can donate to anyone in need.
I have always learned about blood types and acknowledged that they were a big part to our DNA. However, the question, “what is the point of having blood types,” never struck me nor was a question I ever contemplated. This article actually really fascinated me in the way that blood typing had its history all the way back in the 1600s, yet there are still questions being answered today.
The history behind blood transfusions mentioned in this article really surprised me. I didn’t expect this kind of knowledge to be brought up until fifty to a hundred years after the Renaissance. However, in the 1600s, the idea of the ill receiving blood already sprouted, and though the results were disastrous, this was definitely the first jigsaw to the puzzle. I was also surprised by the fact that blood transfusions was the main reason which led scientists to learn about blood typing. In the article, I got to learn that Karl Landsteiner was the first scientist to question why some transfusions failed due to blood clumping. To study this, he used blood combinations, even giving them names of A,B,and C which influenced how we currently name our blood type. Eventually, he was the first scientist to show that only certain blood types could be mixed with each other to avoid clumping and that blood transfusion shouldn’t be a procedure to be performed carelessly.
Furthermore, the article mentions how our early primates have adapted to avoid pathogens destroying blood type antigens, and while a gradual period of time occurred, the primates with rarer blood types lived with a better defense against pathogens. Now, the blood type we own may be the reason why our body is less prone to certain diseases and why certain people can live a more protected life. The author quotes in the last paragraph, “The reason for my blood type may, ultimately, have nothing to do with blood at all.” I guess this might be the answer to the unsolved mystery.
The title of this article made me really question myself and allowed me to continue read with interest. Why do we have different blood types? From reading this article and with prior knowledge I know that the answer is not exactly clear. Earlier, doctors would test blood transfusions on people and results became fatal. Many people became sick, mother's bled during birth, and many died. James Blundell, the British physician, soon realized Humans should only receive human blood. Blundell later learned through the death of his patients that certain humans need blood from other certain humans. At this point in the article I knew that this was the point where he found there are unique types of blood. Later when different blood from different people were tested clumps showed whether or not the two bloods would work together showing certain bloods can go with others. This article allowed me to understand why we have different blood types and why some do not work with others.
Why do we have blood types?
I thought that this article was very interesting. The part of how the different blood types were discovered shocked me. I thought the process would be much more complicated, involving machinery and other sophisticated equipment. I did not expect that it would be as simple as taking the two types of blood and mixing them to check for clumps. I also think that this article explains a concept that is very important to us today. The lives that were saved by blood transfusions would be a very large amount. I also found that debate over the book that told people to eat for their blood type very interesting. When I first read the description that the author had of this book, like that blood types have to do with our evolutionary history and I agreed with him at first. The author even stated the percentage differences among various cultures for the blood types. Then I was convinced that the other end of the argument was right because they had done thousands of tests in which they found no direct correlation with the diet that you eat and your blood type. The health benefits that these people were receiving were merely from the nutritious diet not from the upkeep of their blood. I also understood the whole concept of blood transfusions a lot better from the “shape” reference that the author gave of the various blood types. I really liked this article and I think it answered a lot of the questions that I had on blood types myself
Before reading this article, I had known very little about blood types. In biology class freshman year, we learned the different blood types, but we didn't go into detail on why they are varied in people. I always believed that blood types were first studied in the 1950s. I never would have thought that they were studied before the 1900s. I find it very surprising that there was an experiment to transfer blood from a calf to a human. In this day in age, it seems like common sense that this experiment wouldn't work. However, one has to remember that the technology was far less advanced than nowadays. Also, I find it really cool how Landsteiner founded the A, B, and O blood types by seeing if they clump together. On the other hand, I completely disagree with the blood type diets by Peter D'Adamo. First of all, there is no scientific evidence to back it up. Eating a vegetarian diet will obviously keep you healthy and generally thin regardless of your blood type. It doesn't matter what blood type you have and it doesn't affect what you need to eat in order to be healthy. On the bright side, D'Adamo's book sold seven million copies which means that people cared a lot about their health and wanted to be in good shape. This article was very intriguing, so I want to know more about my blood type. It really sparked an interest in my mind about blood types and why we have them. I finally know the history behind blood types and how they were founded as well as learning that the negative and positive blood types refer to if Rh is present in the blood.
Before this article the last time i had learned about blood transfusions was freshman year. Although I was taught punnett squares to show how people received their blood type, i don't recall learning about the history of blood transfusions. I remember learning that hundred of years ago when people were sick a common practice was to drain the blood out of them. The thought process was to take out the sick blood so the person could recover. However, many times the patients would die of blood loss before recovery could happen. In the 1600's was the start of trial and error blood transfusions. In one experiment a doctor inserted blood from a calf into a man resulting in the patients death. Now it seems preposterous to transfuse blood from another species to humans, but at the time scientists didn't know any better. it wasn't until British physician James Blundell became convinced that doctors shouldn't transfuse "the blood of a brute." Although Blundell was correct about human blood, his patients weren't surviving. The fault was in Blundell's ignorance to the fact the people should only receive blood from certain people. This is how the discovery of blood types occurred. Decades later scientist Karl Landsteiner discovered how some blood clumps when added to other blood, yet some becomes liquid. He separated the blood into types a, b, and c which became o. A blood can only be mixed with a blood , while b blood can only be mixed with b blood. I think the house analogy was useful in the article to aid readers to break down the materiel. What i am skeptical about is the Book by Peter D'Adamo that states that people should eat diets according to their blood type. Although it's an interesting theory, his reasoning is inconclusive. Sure maybe someone living the lifestyle of a vegetarian because of their A blood type may have lower body mass index scores and smaller waists. But then again, anyone regardless of their blood type if they ate healthy and vegetarian would see differences in their waist size and body mass. I do not agree with his book and believe people should stick with a well balanced diet as shown in the food pyramid. A point I strongly agree with is that people have different blood types as a result of natural selections. As some viruses killed hosts with certain antigens, hosts with mutated blood survived. This created the different types we see today. Nature is about survival of the fittest and if having a rarer blood type was beneficial,then natural selection favored them. Overall i found this article both interesting and mind provoking. It gave me the history of blood transfusion and a possible explanation on why there are different blood types.
I found this article to be extremely fascinating. Scientists for years and years have been researching and experimenting to find out more about blood types and why we have them. I learned thy copious amounts of people have died from having blood types that were not compatible with their own being transfused into their bodies. For example, in the 1600s, a French doctor injected calf’s blood into a mentally ill man, which resulted in his death after the second transfusion.
The article also states that a naturopath by the name of Peter D’Adamo, found out that our blood types determine which type foods or diets would be most beneficial for us. For example, people with type A blood would benefit most from a vegetarian diet, people with type B blood would benefit from a rich diary diet, and people with type O blood would benefit from a meat-rich diet.
My blood type is A+, and I just happen to be a vegetarian. So it was really interesting to learn a lot about my blood type and other blood types.
Why do we have blood types?
This article was really fascinating and intriguing to me because I never really thought our blood types had so much background and history and that without paramount discoveries made by people from the past, many people would not even be alive today. At first, I thought blood transfusion was just a simple process that was formulated by scientists decades ago. However, there were actually many complications that took place for many years in order for this process to be perfected. For example, in the 1600s, doctors injected calf's blood into an ill man, but the man got even more sick and eventually died. In addition, the blunder of clumping blood was another complication that scientists went through. Clumping occurred when doctors mixed different blood types into one tube during blood transfusion. As a result, the blood would form into clumps, which would lead to blood clots in the person's body. Many years later, however, Karl Landsteiner abolished this drawback and discovered blood types. This discovery prevented clumping and basically told doctors and scientists that blood given to a patient has to match their blood type. Thanks to this significant figure and discovery, people are successfully transfusing blood today. However, it is quite frightening that a careless mixture of blood types can put a person's life in great danger.
I believe Peter D'Adamo was trying to use the placebo effect when writing his novel, Eat Right 4 Your Type. In this book, he was trying to tell seven million readers that they should go on certain diets according to their blood types. For example, people with Blood Type A should become vegetarians, and people with Blood Type B should go on a meat diet. If people went on these diets, they would be protected from many diseases such as diabetes and cancer. However, D'Adamo did not provide any scientific evidence that this diet actually works. Therefore, this is why I concluded the author of this book integrated the idea of the placebo effect. The placebo effect is the belief that something is useful when it actually is not. For example, if a person is sick and his friend gives him grape juice but tells the person that it is medicine, the person that was given the "medicine" will end up thinking that he or she is getting better. In this case, I think D'Adamo is telling readers that this diet will help even though it will not. Therefore, once readers start going on this diet, they start convincing themselves that this diet is actually helping when it actually is not. Like it was said in the passage, a dairy diet is not helpful to the body at all. It is a good possibility that it is just in the person's head that these blood diets are helpful.
I never really realized that there were great distinctions between Blood Type A, Blood Type B, and Blood Type O. People with Blood Type O have a great advantage because they can receive blood from mostly any donors while people with Blood Type A or B have to receive blood from donors with their corresponding blood type. In addition, Blood Type A and B have two levels of antigens while Blood Type O does not.
The most interesting part of this article to me was near the end where Carl talked about how blood types may be related to diseases and immunity. It was interesting how he said that type O blood seems better protected against severe malaria, which can be caused by two of the five organisms that cause malaria in humans. I thought of how many countries near the equator have more common cases of malaria due to their hot and humid tropical environments. I looked at the frequency of the blood type O allele in these countries and their continents on Wikipedia and saw that the blood type O allele was present from sixty to eighty percent of the population in Africa and ninety to one hundred percent present in South America. Both these continents are located near the equator, but in Alaska, which is in a place where mosquitos can not survive due to the cold, the blood type allele O is also present in ninety to one hundred percent of the population. Also, fourty seven percent of African Americans and fifty three percent of Hispanics have the blood type O positive, according to Blood Centers of the Pacific. It is also interesting that African Americans have a very high chance of not having a blood trait called the Duffy antigen, which is common in other people.. African Americans were found to have an extremely high chance of having the red blood cell phenotype Fy(a-b-) which means that they have Duffy antigen negative. Apparently, this provides some protection from malaria caused by the protozoan P.vivax since there is not a receptor on the red blood cell for it to attach to. However, this does not seem to work part of the time because people without this antigen can still get the disease. Also, since a high percentage of Africans have the allele for sickle cell anemia, which seems to be protective against malaria, those without the Duffy antigen suffer more organ damage due to sickle cell anemia. So, Africans have a high chance of not displaying the Duffy antigen to protect them from malaria but not sickle cell anemia, or they can display it to be protected from sickle cell anemia but not malaria. It may be possible that since humans have developed medicine and brought it to Africa, they may be counteracting natural selection for a blood group that can protect from both malaria and sickle cell anemia.
Reading about the history of blood transfusions in the beginning of the article led me to consider how much intravenous therapy has advanced in the past centuries. IVs were not always the sterile catheters that patients could frantically rip out of their own arms in television dramas. Aside from the tragic fact that the first blood transfusion in the 1600s used calf’s blood for a human, I considered the archaic means of the transfusion. They had been conducted using the quill of a feather and the bladder of an animal for many years. The transfusion must have been overwhelming, as it lacked the slow drip of today’s IV transfusions, and definitely unsanitary. To read and reflect about the history in the article is astounding. Also, after reading this article, I am wondering whether blood types have any correlation with personality traits. For example, because people with the Type A personality are easily wound up, they tend to develop illnesses related to stress like high blood pressure or coronary heart disease. As stated in the article, certain blood types are prone to certain diseases. So is it possible that people with certain blood types are prone to certain personality traits? The Japanese culture suggests the notion that blood types reveal personality, but I have read that many regard its credibility as that of zodiac signs and horoscopes.
Blood types have always been a very unique topic to discuss. Most of us are bound to wonder why we are who we are. Why do we have these blood types and how do they all differ? Growing up I used to see my parents donate blood every year, and every year I wondered what was so special about our type of blood. How was my O positive blood any different from my best friend's AB positive blood? Blood transfusion is still one of the most greatest discoveries in the history of medicine. Yet to this day, we still don't know the why these blood types exist. Carl Zimmer shared the same curiosity, but unlike most of us, he decided to go to the professionals. He spoke to hematologists, geneticists, evolutionary biologists, virologists and nutrition scientists. He learned that blood transfusion can be dated back to the Renaissance. Renaissance doctor, James Blundell, after many experiments, theorized that human patients should only get human blood. Blundell was indeed correct, but when some people's human blood was mixed, clumps began to form. This resulted in different side effects for the human. Blood transfusion was given a bad name up until Landsteiner's discovery.
Karl Landsteiner examined the clumping patterns and discovered that the cause of the clumping was the differences in the blood. He evaluated each persons blood and came up with four potential types: A, B, and C, which was later renamed O. Later on, new types such as AB were also discovered. He messed around with each type of blood until he discovered which would cooperate with which. Unfortunately, Landsteiner's research brought up new questions. They questioned the red blood cells and what specifically caused the clumping. Soon, thanks to Peter D'Adamo's book, and other research by Emmy De Buck and Ahmen El-Sohamy the Blood Type Diet was proposed.
This diet consists of different foods of different blood types.
Zimmer also learned about the ABO gene. This gene is the cause of mutations and has the ability to change a certain blood type. The gene can also encode a protein related to the first discovered blood group system, ABO. Potentially blood types also have the ability to protect us from or cause certain diseases as well. I have discovered that with my own type O blood I am in high risk of ulcers and ruptured Achilles tendons. Blood types are linked to all sorts of things like diseases and evolution. Carl Zimmer enlightened us about why each and every blood type is so unique and special. After reading this article I am still curious about a few topics. What specifically differentiated the blood types? Also, is it possible that there are still unknown mutations in blood types? What advantages are there for different blood types? Can there be a potential blood type that is not a part of the ABO system? Our ancestors, us, and soon the future generations will always question why blood types are such a mystery.
Blood Type Article:
I always have known that my blood type was A+ and that meant i was only able to participate in blood transfusions with other type A people. I was also aware that type O blood was the universal donor. Other than this my knowledge of blood types was lacking. I now know what differentiates the various blood types from one another. They each have their own unique molecular structure of red blood cells. The origins of these blood types and why we have them is still a mystery. Does our blood type have any greater effect on us than who we can transfuse blood with? Through studies the possibility of your blood type effecting your diet has been ruled out, but what else might your blood type affect? This article interested me because I found it very informational and thought-provoking. I was amazed how we seem to know so much more about blood and blood types today than we used to, but at the same time we also seem to know so little about them.
I found out I was Type AB back when I had to get a blood test done. I knew that this meant I could receive from both type A and type B so I was okay in times of crisis. I also knew that type O was the universal DONOR but could not receive from any other type but type O. This is all I remembered from freshman year biology. I now know the reasoning for the separation of the blood types. They each have their own structure. The fact that diet has no effect on the blood type was proven and this raised the question of "What does effect the blood type?" Especially since the origin of this is unknown. The article discusses genes such as the ABO discovered by Zimmer that can cause mutations to change a blood type. There are also risks associated generically with each blood type which I was not aware of.
I found this article to be really interesting because not only did it question something I had never thought to, why we have different blood types, but in searching for the answer to this question, Carl Zimmer explored a variety of areas. He spoke of the history of blood transfusions, how evolution may be responsible for the blood types we have today, and how our blood types determine what we should and shouldn’t eat. It was quite surprising for me to learn that the idea of blood transfusions originated back in the 1600s! As medical knowledge was rudimentary back then, Renaissance doctors blindly experimenting with mixing blood produced disastrous results. It wasn't until the 19th century when British physician James Blundell tried it again with the resolve that mixing blood between humans only rather than introducing animal blood would help patients. He was correct, but half his patients who received transfusions still died. It was later discovered this was because there were indeed 4 different types of blood and that transfusions could only happen between people of a shared blood type. More recently, Peter D’Adamo published a book called Eat Right 4 Your Type, in which he discusses how people have certain blood types based on their ancestors, and how our blood type determines what food we should eat. I found this really fascinating, and apparently people who have followed this Blood Type Diet have had mixed results. This article left me a little unsatisfied as I didn't get the concrete answers I wanted but it did succeed in stirring my curiosity.
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