Genotype-Phenotype Correlation In Iranian Patients With Hb H Disease

Thalassemia is the most common genetic disorder in Iran. Some α-globin genotypes leading to Hb H disease may cause severe anemia and dependence on regular blood transfusions. In this study, 40 patients were analyzed for the molecular basis and the genotype-phenotype correlation of Hb H disease in Iran. α-Globin molecular analysis was performed by polymerase chain reaction (PCR) followed by agarose gel electrophoresis, reverse hybridization test strips or DNA sequencing. The most frequently observed α-globin genotypes were –α^3.7/– –^MED in 10 patients (25%), – –^20.5/α^–5ntα in six patients (15%) and – –^20.5/–α^3.7 in four patients (10%). A subset of the identified Hb H genotypes, including – –^MED/α^CSα, – –^MED/α^PolyA2α and α^CSα/α^CSα, was associated with a need for regular or irregular blood transfusions. Our findings provide a basis for predicting phenotype severity by identifying the Hb H genotype and making more selective decisions for prenatal diagnosis.