Distribution of beta-globin haplotypes among the tribes of southern Gujarat, India.

The present study was carried out in Indo-European speaking tribal population groups of southern Gujarat (India) to elucidate the allelic and haplotypic content of β-globin system in individuals with HbAA genotypes. 6 neutral restriction sites of the β-globin system were analysed and various statistical parameters were estimated to draw meaningful interpretations. All the 6 sites were found to be polymorphic and most were in Hardy-Weinberg Equilibrium in the studied group. Haplotypes were constructed using two different combinations of the 6 restriction sites analysed. Analysis of the 5 sites revealed a set of three predominant haplotypes, '+----', '-++-+' and '-+-++'; and haplotypes '+--', '++-' and '+++' were found to be the most frequent when the 3 sites were used to construct the haplotypes. Haplotypic heterozygosity levels (>83%) observed in the present study group were comparable to those observed in African and Afro-American populations and greater than other world populations. All the ancestral haplotypes, +-----, -++-+, -+-++ and ----+ were found in the study group. The distribution pattern of various haplotypes was consistent with the global pattern. The paucity of comparable data from other Indian populations restricted one from making interpretations about the study group's relationships with other Indian populations but the results were indicative of older population histories or experience of gene flow by the study group and their affinities with populations of southern India.