Write 6 page essay on the topi.
Write 6 page essay on the topic Sickle Cell Anemia.
Individuals with two copies of the mutant version of the hemoglobin gene are likely to develop full-blown sickle cell anemia (Malowany 49).
According to the Darwinian theory of evolution, the existence of sickle cell anemia in only certain geographical regions of the world particularly those prone to malaria is a good example of an evolutionary trade-off during the process of natural selection. In his book, the Origin of the species by natural selection, Darwin particularly outlined the steps of survival for the fittest by arguing that populations often show variations in virtually all traits and that certain variations can improve the survivorship of individuals or organisms(improving their fitness).
On the other hand, the theory also suggests that the frequency of these variations may increase with each generation if they are heritable. The evolutionary trade-off between Sickle cell anemia and Malaria was first highlighted after the discovery that the geographical distribution for the sickle cell allele known as hemoglobin S was virtually overlapping with the geographical distribution of Malaria (Hiren 25). This is particularly based on the notion that sickle cell heterozygote are often resistant to malaria and therefore individuals with sickle cell traits have a survival advantage in Malaria prone regions such as West Africa as compared with individuals with normal hemoglobin.
Malaria is a common tropical disease caused by a protozoan P. falciparum which is largely transmitted through mosquito bites. The protozoa then infect the red blood cells of the victim and multiply thereby becoming available for transfer to other susceptible individuals via mosquito bites. According to Tapper (134), malaria is a disease that has existed in Africa and other tropical regions for several millennia.