Beta-thalassemia

The term thalassemia is derived from the Greek, thalassa (sea) and haima (blood). Beta-thalassemia includes three main forms: Thalassemia Major, variably referred to as "Cooley's Anemia" and "Mediterranean Anemia", Thalassemia Intermedia and Thalassemia Minor also called "beta-thalassemia carrier", "beta-thalassemia trait" or "heterozygous beta-thalassemia". Apart from the rare dominant forms, subjects with thalassemia major are homozygotes or compound heterozygotes for beta0 or beta+ genes, subjects with thalassemia intermedia are mostly homozygotes or compound heterozygotes and subjects with thalassemia minor are mostly heterozygotes.Beta-thalassemia syndromes are a group of hereditary blood disorders characterized by reduced or absent beta globin chain synthesis, resulting in reduced Hb in red blood cells (RBC), decreased RBC production and anemia. Most thalassemias are inherited as recessive traits. Beta-thalassemias can be classified into:- Beta-thalassemia？ Thalassemia major？Thalassemia intermedia？Thalassemia minor- Beta-thalassemia with associated Hb anomalies？ HbC/Beta-thalassemia？ HbE/Beta-thalassemia？ HbS/Beta-thalassemia (clinical condition more similar to sickle cell disease than to thalassemia major or intermedia)- Hereditary persistence of fetal Hb and beta-thalassemia- Autosomal dominant forms- Beta-thalassemia associated with other manifestations？ Beta-thalassemia-tricothiodystrophy？ X-linked thrombocytopenia with thalassemiaBeta-thalassemia is prevalent in Mediterranean countries, the Middle East, Central Asia, India, Southern China, and the Far East as well as countries along the north coast of Africa and in South America. The highest carrier frequency is reported in Cyprus (14%), Sardinia (10.3%), and Southeast Asia [1]. The high gene frequency of beta-thalassemia in these regions is most likely related to the selective pressure from Plasmodium falciparum malaria [1]. Population migration and intermarriage between different ethnic groups has intro