Sickle Disease
Where and why do you think an adaptation occurred that led to the development of sickle cell disease and what is the pathophysiology of the adaptation?
Answer:
Sickle cell disease is thought to have originated in areas with high prevalence of malaria, such as West Africa, as a result of natural selection. The sickle cell mutation, which causes red blood cells to become stiff and sickle-shaped, confers a survival advantage against malaria by reducing the parasite’s ability to infect and multiply within red blood cells.
The pathophysiology of sickle cell disease is caused by a mutation in the beta-globin gene, which results in the production of abnormal hemoglobin. The abnormal hemoglobin molecules tend to stick together, forming rigid, sickle-shaped red blood cells. These sickle-shaped cells have reduced flexibility, which leads to occlusion of small blood vessels, decreased oxygen delivery, and increased risk of tissue damage, inflammation and pain (vaso-occlusive crisis).