Coexistence of rare variant HbD Punjab [α2β2(121(Glu→Gln))] and alpha 3.7 kb deletion in a young boy of Hindu family in West Bengal, India.

Abstract

HbD Punjab is a variant of hemoglobin which occurs as a result of mutation in codon 121 (GAA>CAA) of the β-globin gene, which replaces glutamic acid with glutamine (Glu→Gln). The heterozygous state of HbD does not produce any clinical or hematological symptoms, although its association with HbS and thalassemia produces clinically significant but less severe conditions. The homozygous state produces mild hemolytic anemia and mild to moderate splenomegaly. Alpha-thalassemia is characterized by reduction or absence of the α-globin chains due to deletional or non-deletional mutations of α-globin genes located on chromosome 16. The present study describes a Hindu family where both HbD Punjab and alpha 3.7 kb deletion are present among the members in the heterozygous and double heterozygous state. Comparison of clinical and hematological parameters between the heterozygous and double heterozygous state of HbD and the alpha 3.7 kb deletion is also discussed here. According to our study, the prevalence rate of HbD Punjab is very low, i.e. 0.06%.