September 06, 2007

YAP+ in South Asia

YAP+ defines haplogroup DE in the human Y chromosome phylogeny. Haplogroup D seems confined to a few Asian populations whereas haplogroup E is found in Africans and West Eurasians. Previous studies had determined that D is found at high frequencies among the short-statured isolated populations from the Andaman and Nicobar islands, and this new study indicates that D is also found in mainland South Asia among tribal Indians, albeit at lower frequencies.

Ann Hum Biol. 2007 Sep-Oct;34(5):582-6

YAP insertion signature in South Asia.

Chandrasekar A et al.

A total of 2169 samples from 21 tribal populations from different regions of India were scanned for the Y-chromosome Alu polymorphism. This study reports, for the first time, high frequencies (8-65%) of Y Alu polymorphic (YAP) insertion in northeast Indian tribes. All seven Jarawa samples from the Andaman and Nicobar islands had the YAP insertion, in conformity with an earlier study of Andaman Islanders. One isolated case with haplotype E* was found in Dungri Bhill, a western Indian population, while YAP insertion in northeast India and Andaman tribes was found in association with haplotype D* (M168, M174). YAP insertion frequencies reported in the mainland Indian populations are negligible, according to previous studies. Genetic drift may be the causative factor for the variable frequency of the YAP insertion in the mainland populations, while the founder effect may have resulted in the highest incidence of haplotype D among the Andaman Islanders. The results of YAP insertion and the evidence of previous mtDNA studies indicate an early out of Africa migration to the Andaman and Nicobar Islands. The findings of YAP insertion in northeast Indian tribes are very significant for understanding the evolutionary history of the region.

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