Genetics of sickle cell - Assignment Example

Those with a single inherited gene do not suffer from the disease but possess the sickle cell trait that can be transferred to their children. The genetics of sickle cell disease are discussed here, with respect to the inheritance of the disease, its molecular genetics and genetic variation. SCD is a multi-system disease in which episodes of acute illness occur along with progressive organ damage (Rees, Williams and Gladwin, 2010). It is among the worlds most commonly occurring severe monogenic disorders.

Herrick first described the occurrence of sickle shaped red blood cells in 1910 (Cited in Rees, Williams and Gladwin, 2010). Pauling et al. (1949) later identified that sickle haemoglobin has electrophoretic abnormalities, therefore terming SCD as a molecular disease. Normal red blood cells can pass freely through capillaries while abnormal sickle shaped red blood cells cannot. Sickle shaped red blood cells are long and sticky, with tapering ends. Figure 1 shows the difference between normal RBC and sickle cells.

Sickle cells tend to bunch up while some break down, stopping or slowing down the flow of blood (Peterson, 2008). Sickle cells do not receive enough oxygen and their waste products cannot be carried away. Because of the buildup of waste products and lack of oxygen, sickle cell disease causes great pain and even death. As per the National Institutes of Health (NIH) estimates, around 72,000 Americans, most of which are African Americans, suffer from sickle cell anemia (Peterson, 2008). Worldwide, there are millions of people inflicted with the disease, which commonly occurs in warm areas near large bodies of water (Peterson, 2008).

While the occurrence sickle shaped red blood cells was discovered by James Herrick and their abnormal electrophoretic mobility was identified by Linus Pauling and colleagues, it was Vernon Ingram who discovered that the disease resulted from a