42663_Bergstrom,A_2016.pdf (1.06 MB)
Download fileDeep Roots for Aboriginal Australian Y Chromosomes
journal contribution
posted on 2023-02-01, 01:39 authored by A Bergstroem, Nano NagleNano Nagle, Yuan Chen, Shane McCarthy, MO Pollard, Qasim Ayub, Stephen Wilcox, Leah WilcoxLeah Wilcox, Roland OorschotRoland Oorschot, P McAllister, Leslie Williams, Yali Xue, R John Mitchell, Chris Tyler-SmithAustralia was one of the earliest regions outside Africa to be colonized by fully modern humans, with archaeological evidence for human presence by 47,000 years ago (47 kya) widely accepted [1, 2]. However, the extent of subsequent human entry before the European colonial age is less clear. The dingo reached Australia about 4 kya, indirectly implying human contact, which some have linked to changes in language and stone tool technology to suggest substantial cultural changes at the same time [3]. Genetic data of two kinds have been proposed to support gene flow from the Indian subcontinent to Australia at this time, as well: first, signs of South Asian admixture in Aboriginal Australian genomes have been reported on the basis of genome-wide SNP data [4]; and second, a Y chromosome lineage designated haplogroup C-, present in both India and Australia, was estimated to have a most recent common ancestor around 5 kya and to have entered Australia from India [5]. Here, we sequence 13 Aboriginal Australian Y chromosomes to re-investigate their divergence times from Y chromosomes in other continents, including a comparison of Aboriginal Australian and South Asian haplogroup C chromosomes. We find divergence times dating back to ∼50 kya, thus excluding the Y chromosome as providing evidence for recent gene flow from India into Australia.