Resistance to Malaria with Sickle Cell Anemia
In AP biology in my junior year at Judge Memorial I learned what I think is the most interesting thing I've ever learned as a student here. We were studying all about genetics and this topic came along with mutations and natural selection. One of the topics that came up was that of the relationship of sickle cell anemia to malaria resistance. In areas where malaria is prominent and has been for decades, scientists have noticed that there has been a consequential increase in the prominence of sickle cell anemia. This ended up being a result of the life cycle of malaria and how it spends some of its life cycle in the blood cells. Those that were heterozygous for sickle cell anemia (have one recessive allele) were not dying from malaria even if they were contracting the disease. They did not have sickle cell anemia (it's a double recessive trait), but their blood cells were changed as a result of the one recessive allele. Over time more and more recessive alleles that code for sickle cell anemia were passed on because these people were the ones surviving in areas where malaria was a major killer. As a result more children are born with sickle cell anemia(usually a fatal disease) however less people were dying from malaria. It became an inherited resistance. Of course, this comes with a cost of more children with the two recessive alleles, but I thought it was very interesting how the gene pool had changed as a result of malaria prevalence. Malaria is selecting for sickle cell anemia. I feel like this is something that not a lot of people know and I am glad that I was able to learn it. I found it very interesting.