The genetic heritage of the earliest settlers persists both in Indian tribal and caste populations
The genetic heritage of the earliest settlers persists both in Indian tribal and caste populations
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DOI：
10.1086/346068
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发表时间：
2003-02-01
影响因子：
9.8
通讯作者：
Villems, R
中科院分区：
文献类型：
--
作者：
Kivisild, T;Rootsi, S;Villems, R
来自印度南部的两个部落群体的Chenchus和Koyas的线粒体DNA（mtDNA），Y染色体和一个常染色体位点的变异进行了分析，并与来自印度不同地区的六个种姓群体，以及与西方和中亚人进行了比较。在mtDNA系统发育分析中，Chenchus和Koyas合并在单倍群M和N的印度特有分支上，这些单倍群覆盖了整个次大陆不同社会等级的人群。合并时间表明早在晚更新世解决南亚，并建议没有完全取代这些定居者后来的迁移。H、L和R2是印度主要的Y染色体单倍型群，在种姓和部落人群中都存在，在次大陆以外很少发现。单倍型群R1 a，以前与假定的印度-雅利安入侵有关，在旁遮普发现的频率最高，但在Chenchu部落也有相对较高的频率（26%）。这一发现，以及较高的R1 a相关的短串联重复序列的多样性在印度和伊朗相比，欧洲和中亚，表明南亚和西亚可能是这个单倍型群的来源。21号染色体MX 1基因座的单倍型频率将Koyas和Chenchus以及沿着印度种姓群体与欧洲和东亚人群区分开来。两者合计，这些结果表明，印度部落和种姓人口主要来自更新世南亚和西亚人相同的遗传遗产，并已收到有限的基因流从外部地区全新世以来。原始线粒体DNA和Y染色体创始人的地理分布表明，这些来自非洲的南亚更新世沿海定居者可能为欧亚大陆东部和西部独特基因库的后续分化提供了接种物。
Two tribal groups from southern India-the Chenchus and Koyas-were analyzed for variation in mitochondrial DNA (mtDNA), the Y chromosome, and one autosomal locus and were compared with six caste groups from different parts of India, as well as with western and central Asians. In mtDNA phylogenetic analyses, the Chenchus and Koyas coalesce at Indian-specific branches of haplogroups M and N that cover populations of different social rank from all over the subcontinent. Coalescence times suggest early late Pleistocene settlement of southern Asia and suggest that there has not been total replacement of these settlers by later migrations. H, L, and R2 are the major Indian Y-chromosomal haplogroups that occur both in castes and in tribal populations and are rarely found outside the subcontinent. Haplogroup R1a, previously associated with the putative Indo-Aryan invasion, was found at its highest frequency in Punjab but also at a relatively high frequency (26%) in the Chenchu tribe. This finding, together with the higher R1a-associated short tandem repeat diversity in India and Iran compared with Europe and central Asia, suggests that southern and western Asia might be the source of this haplogroup. Haplotype frequencies of the MX1 locus of chromosome 21 distinguish Koyas and Chenchus, along with Indian caste groups, from European and eastern Asian populations. Taken together, these results show that Indian tribal and caste populations derive largely from the same genetic heritage of Pleistocene southern and western Asians and have received limited gene flow from external regions since the Holocene. The phylogeography of the primal mtDNA and Y-chromosome founders suggests that these southern Asian Pleistocene coastal settlers from Africa would have provided the inocula for the subsequent differentiation of the distinctive eastern and western Eurasian gene pools.