Complex paternal origins of the Han Chinese（复杂的汉族父系起源）

原文：http://eurogenes.blogspot.com/2014/08/complex-paternal-origins-of-han-chinese.html

There's an intriguing new  paper  at the AJHB on the paternal ancestry of a population from Iron Age China(人类生物学美国杂志上有一篇关于一个中国族群父系祖先耐人寻味的文章）. It argues that the Han Chinese are the result of fairly recent admixture events, with Y-chromosome haplogroup Q1a1 entering the ancestral territory of the Han, the Central Plain of China, only around 3,000 years ago from the northwest. (汉人是相当近时期混合结果，是随着Y-Q1a1大约3000年前从西北进入中原时期开始） It's probably a sign of things to come, not only for the Han but many populations generally thought to be genetically homogeneous.

Note also how the Y-chromosome haplogroups appear to be associated with different burial customs and inferred social status. Q1a1 was found in the remains of three aristocrats and eight commoners, most of them buried in the extended prostrate position typical of Bronze and Iron Age steppe nomads of what is now western China. Most of the other remains were buried in the extended supine position, characteristic of the populations of the Chinese Central Plain at the time. I've put the details into a spreadsheet here.

It'll be interesting to learn about the genome-wide genetic structure of the people who introduced haplogroup Q1a1 into the ancestral Han gene pool（有兴趣的是谁把Q1a1带进汉族祖先基因池中）. Were they perhaps in large part of Ancient North Eurasian (ANE) origin? The reason I say this is because Q is the most common Y-chromosome haplogroup in the Americas, where ANE peaks today. It's also the sister clade of haplogroup R, which is the paternal marker of Mal'ta boy, or the MA-1 genome, the main reference sample for ANE.

Indeed, haplogroup R was expanding in a big way across Europe and West and Central Asia at about the same time as Q1a1 in China. It also probably came from the steppe and was in all likelihood associated with the spread of ANE deep into Europe.

1. Objectives: Y chromosome haplogroup Q1a1 is found almost only in Han Chinese populations. However, it has not been found in ancient Han Chinese samples until now. Thus, the origin of haplogroup Q1a1 in Han Chinese is still obscure（汉族Q1a1的起源仍然是模糊的）. This study attempts to provide answer to this question, and to uncover the origin and paternal genetic structure of the ancestors of the Han Chinese.
2. Methods: Eighty-nine ancient human remains that were excavated from the presumed geographic source of the Han Chinese and dated to approximately 3,000 years ago were treated by the amelogenin gene polymerase chain reaction test, to determine their sex. Then, Y chromosome single nucleotide polymorphisms were subsequently analyzed from the samples detected as male.
3. Results: Samples from 27 individuals were successfully amplified. Their haplotypes could be attributed to haplogroups N, O*, O2a, O3a, and Q1a1. Analyses showed that the assigned haplogroup of each sample is correlated to the suspected social status and observed burial custom associated with the sample.
4. Conclusions结论: The origins of the observed haplotypes and their distribution in present day Han Chinese and in the samples suggest that haplogroup Q1a1 was probably introduced into the Han Chinese population approximately 3,000 years ago(Q1a1进入汉族人群大约在3000年前）.

• Hengbei site横北遗址(Peng kingdom cemetery of Western Zhou Dynasty 西周倗国), Jiang County, Shanxi, 2800-3000YBP: 9 Q1a1-M120, 2 O2a-M95, 1 N, 4 O3a2-P201, 2 O3, 4 O*^[57]
  • In another paper, the social status of those human remains of ancient Peng kingdom are analyzed. aristocrats贵族: 3 Q1a1(prostrate俯身葬 2, supine仰身葬 1), 2 O3a(supine 2), 1 N(prostrate) / commoners平民 : 8 Q1a1(prostrate 4, supine 4), 3 O3a(prostrate 1, supine 2), 3 O*(supine 3) / slaves奴隶: 3 O3a, 1 O3a3，2 O2a, 1 O*^[58]
  • (cf)Pengbo, Monarch of Peng Kingdom is estimated as Q-M120.（倗伯估计是Q-M120)