Defining the allelic variants of HLA A19 in the western Indian population.

The population of western India is described as Australoid or proto-Australoid (elements) with Indo-Aryan racial admixture. The present study was undertaken to investigate the genetic diversity of human leukocyte antigen (HLA A19) in Western Indians, and to determine the frequency distribution of its molecular subtypes at the population level. The study revealed a high occurrence of A*3303 (56%) in this population along with other common oriental alleles. A*33 has been commonly observed in Asian Indians (18.1%), Hanza-Burush (15.7%), Punjabis (13.9%), and Japanese (11.2%) populations. A*33 has been reported with low frequencies among the Australasians, East European (Czech), North African (Noba), and Eastern Europeans (Slovenian). Significantly we observed a low frequency of A*29 and A*74 when compared with other populations among the A19 repertoire. Prevalence of HLA A*3303 at very high frequencies among Western Indians may be a consequence of the founder effect, racial admixture, or selection pressure due to environmental factors among this population.