Premarital Screening for Thalassemia and Sickle Cell Anemia - Essay Example

Many hemoglobinopathies are inherited disorders. Thalassemia and Sickle Cell Disease are the most prevalent hemoglobinopathies. Both these conditions are inherited as autosomal recessive disorders. They share standard features like premature destruction of red blood cells and elevated erythropoietin levels in the marrow and other sites to compensate for the loss of red cells and accumulation of the products of hemoglobin catabolism due to increased rate of red cell destruction (Aster, 2007). Thalassemias are a group of heterogeneous inherited disorders caused by genetic defects as a consequence of which decreased synthesis of either the alpha or beta chain of HbA occurs (Aster, 2007, pg.632). When the deficient synthesis of the beta chain occurs, it is known as beta-thalassemia and when alpha synthesis is affected, it is known as alpha-thalassemia.

Sickle cell anemia is a type of disease characterized by the production of defective hemoglobins because of which sickling of red cells occurs in certain conditions like deoxygenation (Aster, 2007, pg.628). The WHO has estimated that about 7% of the world population are carriers of inherited hemoglobin disorders and that about 3 to 4 hundred thousand babies are being born each year with severe forms of these diseases (Weatherall, 2001). About 3% of the world population is carriers of a beta thalassemia mutation (Ghotbi & Tsukatani, 2002).

Though globally, carriers of thalassemia are more than the carriers of sickle cell anemia, the number of affected births of sickle cell anemia is more than thalassemia due to the higher frequency of sickle cell genes in certain areas (WHO Secretariat Report, 2006). These conditions are prevalent all over the world with the highest incidences noticed in tropical regions (Refer to tables-1 and 2). The gene for sickle cell anemia is distributed widely in the region areas-Saharan Africa, the Middle East, and the Indian subcontinent.

In these regions, it has been estimated that the carrier frequencies range from 5% to 40% or more of the population (Weatherall, 2001). Forty percent prevalence is seen in some regions of Africa (Schwarting, 2007).