Post-last glacial maximum expansion of Y-chromosome haplogroup C2a-L1373 in northern Asia and its implications for the origin of Native Americans.


Sun J(1)(2), Ma PC(3), Cheng HZ(1), Wang CZ(4), Li YL(5), Cui YQ(3), Yao HB(6), Wen SQ(7)(8), Wei LH(1)(8).
Author information:
(1)Department of Anthropology and Ethnology, Institute of Anthropology, Xiamen University, Xiamen, China.
(2)Xingyi Normal University for Nationalities, Xingyi, China.
(3)School of Life Sciences, Jilin University, Changchun, China.
(4)Department of Radiology, The First Affiliated Hospital of Shantou University Medical College, Shantou, China.
(5)School of Ethnology and Anthropology, Inner Mongolia Normal University, Hohhot, China.
(6)Key Laboratory of Evidence Science of Gansu Province, Gansu University of Political Science and Law, Lanzhou, China.
(7)Institute of Archaeological Science, Fudan University, Shanghai, China.
(8)B&R International Joint Laboratory for Eurasian Anthropology, Fudan University, Shanghai, China.


OBJECTIVES: Subbranches of Y-chromosome haplogroup C2a-L1373 are founding paternal lineages in northern Asia and Native American populations. Our objective was to investigate C2a-L1373 differentiation in northern Asia and its implications for Native American origins. MATERIALS AND METHODS: Sequences of rare subbranches (n = 43) and ancient individuals (n = 37) of C2a-L1373 (including P39 and MPB373), were used to construct phylogenetic trees with age estimation by BEAST software. RESULTS: C2a-L1373 expanded rapidly approximately 17.7,000-14.3,000 years ago (kya) after the last glacial maximum (LGM), generating numerous sublineages which became founding paternal lineages of modern northern Asian and Native American populations (C2a-P39 and C2a-MPB373). The divergence pattern supports possible initiation of differentiation in low latitude regions of northern Asia and northward diffusion after the LGM. There is a substantial gap between the divergence times of C2a-MPB373 (approximately 22.4 or 17.7 kya) and C2a-P39 (approximately 14.3 kya), indicating two possible migration waves. DISCUSSION: We discussed the decreasing time interval of "Beringian standstill" (2.5 ky or smaller) and its reduced significance. We also discussed the multiple possibilities for the peopling of the Americas: the "Long-term Beringian standstill model," the "Short-term Beringian standstill model," and the "Multiple waves of migration model." Our results support the argument from ancient DNA analyses that the direct ancestor group of Native Americans is an admixture of "Ancient Northern Siberians" and Paleolithic communities from the Amur region, which appeared during the post-LGM era, rather than ancient populations in greater Beringia, or an adjacent region, before the LGM.