Prevalence of α+-Thalassemia in the Scheduled Tribe and Scheduled Caste Populations of Damoh District in Madhya Pradesh, Central India

Abstract

This study was carried out to ascertain the allelic frequency of α+-thalassemia (α+-thal) in Scheduled caste and scheduled tribe populations of the Damoh district of Madhya Pradesh, India. Random blood samples of Scheduled tribe (267) and Scheduled caste (168), considering the family as a sampling unit, were analyzed for the presence of the –α3.7 (rightward) (NG_000006.1: g.34164_37967del3804) and –α4.2 (leftward) (AF221717) deletions. α+-Thal was significantly higher in the Scheduled tribals (77.9%) as compared to the scheduled caste population (9.0%). About 58.0% scheduled tribals carried at least one chromosome with the –α3.7 deletion and 20.0% scheduled tribals carried the –α4.2 deletion. Frequency for the –α3.7 allele was 0.487 in the scheduled tribal populations in comparison to 0.021 in scheduled castes. Allelic frequency for –α4.2 was 0.103 and 0.024, respectively, in the above communities. No Hardy-Weinberg equilibrium for α-thal gene (p < 0.05) was detected in the tribal population, indicating the presence of selection pressures in favor of α-thal mutation and adaptation.