Sickle cell anemia is an inherited blood disorder, characterized primarily by chronic anemia and periodic episodes of pain. The cause of sickle cell anemia is a genetic disorder in which the hemoglobin is defective. When the hemoglobin molecules gives up their oxygen, some will cluster together. This forms long, rod-like structures which cause the red blood cells to stiffen and assume a sickle shape. With the deformity, the cells cannot squeeze through the blood vessels, depriving organs and tissues of oxygen
Normal blood cells live for about one hundred twenty day in the blood, while the defective sickled cells live only ten to twenty. Because of their shortened lifespan, the blood is constantly deficient in red blood cells, a condition known as anemia.
Sickle cell anemia is a genetic disorder that resulted from a mutation which occurred thousands of years ago in Africa, the Mediterranean basin, the Middle East, and India.
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based on http://www.understandingrace.org/humvar/s...
English: Description Malaria versus sickle-cell tr...At the time, deadly malaria epidemics cause great numbers of deaths. Those who inherited the sickle cell gene had an advantage: unlike children with normal red blood cells, they could survive malaria, and grow old enough to have their own offsprings, thus passing along the mutation. As the population migrated, so did the mutation. In countries where malaria is not a problem, like the United States, the sickle cell mutation is disorder, no longer providing a survival trait of value. Instead it is a serious threat. If a child inherits two of the recessive sickle cells genes, they will be born with sickle cell anemia .In the United States alone, sickle cell anemia affects approximately seventy-two thousand people, most of whose ancestors descended from Africa. About two million Americans carry the gene for sickle cell anemia.
The clinical course of sickle cell anemia does not follow...