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29# 天天向上  
不知所云,只能说你嘴尖皮厚而已
baiyueren 发表于 2017-1-15 13:03
哦,就我看来很多问题根本不是问题,只需要稍微观察一下所谓 样本人群体质就能发现问题,当然了很多人坚决不肯这样做
The Combined Landscape of Denisovan and Neanderthal Ancestry in Present-Day Humans: Current Biology  http://www.cell.com/current-biology/pdf/S0960-9822(16)30247-0.pdf---------------------------
要点概述:
•Denisovan admixture into modern humans occurred after Neanderthal admixture
•There is more Denisovan ancestry in South Asians than expected from current models
•Denisovan ancestry has been subject to positive and negative selection after admixture
•Male infertility most likely occurred after modern human interbreeding with Denisovans
Summary
Some present-day humans derive up to ~5% [ 1 ] of their ancestry from archaic Denisovans, an even larger proportion than the ~2% from Neanderthals [ 2 ]. We developed methods that can disambiguate the locations of segments of Denisovan and Neanderthal ancestry in present-day humans and applied them to 257 high-coverage genomes from 120 diverse populations, among which were 20 individual Oceanians with high Denisovan ancestry [ 3 ]. In Oceanians, the average size of Denisovan fragments is larger than Neanderthal fragments, implying a more recent average date of Denisovan admixture in the history of these populations (p = 0.00004). We document more Denisovan ancestry in South Asia than is expected based on existing models of history, reflecting a previously undocumented mixture related to archaic humans (p = 0.0013). Denisovan ancestry, just like Neanderthal ancestry, has been deleterious on a modern human genetic background, as reflected by its depletion near genes. Finally, the reduction of both archaic ancestries is especially pronounced on chromosome X and near genes more highly expressed in testes than other tissues (p = 1.2 × 10−7 to 3.2 × 10−7 for Denisovan and 2.2 × 10−3 to 2.9 × 10−3 for Neanderthal ancestry even after controlling for differences in level of selective constraint across gene classes). This suggests that reduced male fertility may be a general feature of mixtures of human populations diverged by >500,000 years.


     可惜原文要交钱,以后有机会再下吧~
物格而后知至,知至而后意诚,意诚而后心正,心正而后身修,身修而后家齐,家齐而后国治,国治而后天下平...
Denisovan Ancestry in East Eurasian and Native American Populations. - PubMed - NCBI  https://www.ncbi.nlm.nih.gov/pubmed/26104010Qin P1, Stoneking M2.
Author information


AbstractAlthough initial studies suggested that Denisovan ancestry was found only in modern human populations from island Southeast Asia and Oceania, more recent studies have suggested that Denisovan ancestry may be more widespread. However, the geographic extent of Denisovan ancestry has not been determined, and moreover the relationship between the Denisovan ancestry in Oceania and that elsewhere has not been studied. Here we analyze genome-wide single nucleotide polymorphism data from 2,493 individuals from 221 worldwide populations, and show that there is a widespread signal of a very low level of Denisovan ancestry across Eastern Eurasian and Native American (EE/NA) populations. We also verify a higher level of Denisovan ancestry in Oceania than that in EE/NA; the Denisovan ancestry in Oceania is correlated with the amount of New Guinea ancestry, but not the amount of Australian ancestry, indicating that recent gene flow from New Guinea likely accounts for signals of Denisovan ancestry across Oceania. However, Denisovan ancestry in EE/NA populations is equally correlated with their New Guinea or their Australian ancestry, suggesting a common source for the Denisovan ancestry in EE/NA and Oceanian populations. Our results suggest that Denisovan ancestry in EE/NA is derived either from common ancestry with, or gene flow from, the common ancestor of New Guineans and Australians, indicating a more complex history involving East Eurasians and Oceanians than previously suspected.

物格而后知至,知至而后意诚,意诚而后心正,心正而后身修,身修而后家齐,家齐而后国治,国治而后天下平...
https://www.sciencedaily.com/releases/2013/11/131120143631.htm
http://blog.sina.com.cn/s/blog_d963b0de0102x6jv.html
http://www.bbioo.com/news/20131124102189.html
一、Mal'ta男孩
1.Mal’ta男孩所属人群是印第安人的祖先,也解释了为什么一些印第安人的骨骼(如肯纳威克人)上拥有某些欧洲人的特征。印第安人的祖先是从西伯利亚迁移来的,而不是此前部分人认为从欧洲直接迁徙而来。印第安人的祖先可能在24000年前的某一天通过白令陆桥——俄罗斯最东北部和阿拉斯加——由此占领了阿拉斯加和美洲,这比我们通常认为的、考古材料所显示的14500年前要早得多。
3.与今天的美洲土著和某些西欧亚大陆人非常相近,尤其是与中亚、南亚和欧洲的某些群体联系更为密切。他的基因还与生活在欧陆俄罗斯、捷克甚至德国的其他冰河世纪西欧亚大陆人有关系。我们认为这些冰河时代的人拥有超强的移动能力,并保持了一个广泛的基因库,其从中西伯利亚一直向西传播到中欧。
二、墨西哥水下洞穴发现一万年前男孩骨骼
http://tech.sina.com.cn/d/2010-08-26/08044589837.shtml
本帖最后由 baiyueren 于 2017-1-16 10:43 编辑

44# Hanhe
马尔他所属人群,不是任何现代大人群的祖先,而只是中亚某些小群体,比如布鲁沙斯克人的祖先。
但是你说对了一点,就是在常染方面,肯尼威克人和克洛维斯人,应该是所谓的ANE(古西伯利亚)与现代西伯利亚-远东-美洲人群之间的桥梁。没有象肯尼威克这种Y-Q、mt-X样本的加入,所谓的ANE的准确划分也是堪忧的。
马耳他人群,看起来只是2万多年前中-南亚地区原始人群遗传构成的一个快照。我们不能在哪里捡到一块骨头,就说他是某某族群的祖先。事实上马耳他和K14都是纯血族群间的混血儿,而且很可能没有直系的后代。只能说他们的纯血近亲后代一直生存到今天,并有一些繁衍壮大而已。
NRY: O2a1c1a1a1a1a1a1-002611,F11,F17,F856,F1495(源自粤西云浮)
mtDNA:B4d1(源自浙北慈溪)
百越人的人类学文集 http://blog.sina.com.cn/baiyueren
本帖最后由 Hanhe 于 2017-1-16 11:36 编辑

刚才断网,我有几点疑问:
1.资料上说的有些差别。也没有人论及陪葬类似中国上古人;
2.由Mal'ta男孩推出的印第安人(最少有两批)与欧洲人、亚洲人的遗传与迁徙问题,好像还不能解释全部疑问;
3.几年前发现的这个墨西哥男孩有DNA检测结果吗?
4.20#
Oymyakon人是否与美洲迁徙路线有关?他们也没有Y-DNA信息吧?
上面说的墨西哥小孩“早于现在已知的克洛维斯群体,据说在冰河时代末,该群体来自亚洲北部,通过白令海峡,到达美洲”。
The Combined Landscape of Denisovan and Neanderthal Ancestry in Present-Day Humans: Current Biology  http://www.cell.com/current-biology/pdf/S0960-9822(16)30247-0.pdf---------------------------
要点概述:
•Denisovan admixture into modern humans occurred after Neanderthal admixture
•There is more Denisovan ancestry in South Asians than expected from current models...
imvivi001 发表于 2017-1-16 00:22
sankararaman-reich的这篇成果很重要,看来南亚-巴基斯坦-BMAC地区-欧亚大草原是早期东欧亚低纬度人群北上的主要通道,再次提示MA1以及亚美人群(x大洋洲x西藏高原x岛屿东南亚)身上丹人血统的可能来源之一(极有可能是最主要的来源)。
    从目前亚美人群(x大洋洲x西藏高原x岛屿东南亚)观察到的微量的丹人血统(平均约0.1~0.2%,个别美洲人群稍多一点),结合亚美人群普遍存在的ANE血统,可以推测:1、亚美人群与澳美人群之间的基因交流主要是前者向后者输血,后者几乎没有向前者输血;2、尽管澳巴地区的丹人有可能起源于西伯利亚,可是在出非洲的欧亚人群来到西伯利亚时,当地的丹人有可能已经南下避寒或已经灭绝,之后ANE古人的丹人血统,可能来自欧亚东西大分离之后南亚人群北上所带来的。这样,亚美人群微量的丹人血统绝大部分应该是来自与北方的ANE人群的混合所带来的。
     因为原文需要购买,暂时下不到原文,只找到根据原文整理的丹人血统全球分布图A world map of Neanderthal and Denisovan ancestry in modern humans  https://phys.org/news/2016-03-wo ... ncestry-modern.html,如下:

物格而后知至,知至而后意诚,意诚而后心正,心正而后身修,身修而后家齐,家齐而后国治,国治而后天下平...
本帖最后由 baiyueren 于 2017-1-16 12:39 编辑

49# imvivi001
不敢苟同,我认为ANE其实是以Y-Q,mt-X为主的祖先人群,换言之ANE的主体就是后来肯尼威克人的祖先。
马耳他男孩的Y-R*,mt-U,说明他性染基本上是古西欧亚祖先的遗传,当时是Q/R刚从P中分化出来之后几Kya,所以停留在在中-南亚的马耳他人群与刚分离的Y-Q为主体的ANE有较多的血缘交流,或者说交叉混血。但是这不代表向西扩散的Y-R1也是这种情况。

丹人的话,如果马耳他男孩有10%的丹人基因得到确认,那么只能说明丹人基因混入现代人的地点就在南亚-南陆一带。不能认为丹人是在西伯利亚发现的,就是在西伯利亚发生的混血,而很可能是古代人骨和DNA在寒冷地带更容易保存而已。
还有就是现在中国很多的5万年前的古人类,包括马坝人,南京人等的系属在遗传方面都还没有得到确认,不能排除他们属于丹人序列的可能性。
NRY: O2a1c1a1a1a1a1a1-002611,F11,F17,F856,F1495(源自粤西云浮)
mtDNA:B4d1(源自浙北慈溪)
百越人的人类学文集 http://blog.sina.com.cn/baiyueren
49# imvivi001
不敢苟同,我认为ANE其实是以Y-Q,mt-X为主的祖先人群,换言之ANE的主体就是后来肯尼威克人的祖先。
马耳他男孩的Y-R*,mt-U,说明他性染基本上是古西欧亚祖先的遗传,当时是Q/R刚从P中分化出来之后 ...
baiyueren 发表于 2017-1-16 12:37
我认为单倍群P1所对应的应该就是ANE或者ANE成分的前身,P1应该是最早在东南亚四万五千年前先与MS分离,再与P2分离,进入南亚到中亚一带后分化为R、Q1a、Q1b,这时对应的线粒体为X,在进入北部欧亚后遇到当地的狩猎采集人群,才从他们那里获得了母系线粒体U,及类WHG成分。在此之前,P1单倍群的人群可能和古代欧洲狩猎采集人群的成分还没有太大联系。
C-M130交流群:542136235
我认为单倍群P1所对应的应该就是ANE或者ANE成分的前身,P1应该是最早在东南亚四万五千年前先与MS分离,再与P2分离,进入南亚到中亚一带后分化为R、Q1a、Q1b,这时对应的线粒体为X,在进入北部欧亚后遇到当地的狩猎 ...
豢龙氏 发表于 2017-1-16 13:17
有一些道理,我也认为R最初不是古西欧亚成分,但后来西迁成为了现代西欧亚成分。
NRY: O2a1c1a1a1a1a1a1-002611,F11,F17,F856,F1495(源自粤西云浮)
mtDNA:B4d1(源自浙北慈溪)
百越人的人类学文集 http://blog.sina.com.cn/baiyueren
本帖最后由 baiyueren 于 2017-1-16 19:22 编辑

把我对马耳他男孩所处时期的Y单倍群分布的假想做个图示。
2.5万年前亚洲.png
1

评分次数

  • imvivi001

NRY: O2a1c1a1a1a1a1a1-002611,F11,F17,F856,F1495(源自粤西云浮)
mtDNA:B4d1(源自浙北慈溪)
百越人的人类学文集 http://blog.sina.com.cn/baiyueren
把我对马耳他男孩所处时期的Y单倍群分布的假想做个图示。
baiyueren 发表于 2017-1-16 15:12
NO的共祖时间是三万七千年左右,两万五千年的时候N单倍群甚至可能已经活动到了很北方的地区,O单倍群在2.5万年前也早已分化成O1a、O1b、O2,甚至一些下游支系,不可能只局促在那么一个角落
C-M130交流群:542136235
本帖最后由 baiyueren 于 2017-1-16 15:41 编辑
NO的共祖时间是三万七千年左右,两万五千年的时候N单倍群甚至可能已经活动到了很北方的地区,O单倍群在2.5万年前也早已分化成O1a、O1b、O2,甚至一些下游支系,不可能只局促在那么一个角落
豢龙氏 发表于 2017-1-16 15:36
我这只是一个图示。2.5万年前田园洞人就沿着海岸线活动到了北京,但是环境一变化他们就灭绝了,所以对当时的渔猎采集者来说,北方不是NO人群可以长期稳定居住的地区。因为他们以鱼为主食。
同理,西伯利亚对马耳他和乌斯季人来说也是如此。
NRY: O2a1c1a1a1a1a1a1-002611,F11,F17,F856,F1495(源自粤西云浮)
mtDNA:B4d1(源自浙北慈溪)
百越人的人类学文集 http://blog.sina.com.cn/baiyueren
44# Hanhe
刚查到一篇论文《the genome of a late pleistocene human from a clovis burial site in western montana》。已经测出美国蒙大拿Anzick遗址克洛维斯人的Y是Q-L54*(xM3)。肯尼威克人的Q-M3,是L54的下游。
1

评分次数

NRY: O2a1c1a1a1a1a1a1-002611,F11,F17,F856,F1495(源自粤西云浮)
mtDNA:B4d1(源自浙北慈溪)
百越人的人类学文集 http://blog.sina.com.cn/baiyueren
55# baiyueren
有大Q天空坐镇本坛,克洛维斯人与肯尼威克人的y类型早就不是新闻了~
物格而后知至,知至而后意诚,意诚而后心正,心正而后身修,身修而后家齐,家齐而后国治,国治而后天下平...
56# imvivi001
本帖最后由 imvivi001 于 2017-1-16 23:49 编辑

这条新闻比较新,与本楼Lazaridis-Lipson-Reich最新的观点遥相呼应~The Simons Genome Diversity Project: 300 genomes from 142 diverse populations  http://www.nature.com/nature/journal/v538/n7624/full/nature18964.html

Swapan Mallick, Heng Li, Mark Lipson, Iain Mathieson, Melissa Gymrek, Fernando Racimo, Mengyao Zhao, Niru Chennagiri, Susanne Nordenfelt, Arti Tandon, Pontus Skoglund,
Iosif Lazaridis, Sriram Sankararaman, 付巧妹,
Nadin Rohland, Gabriel Renaud, Yaniv Erlich, Thomas Willems, Carla Gallo,
Jeffrey P. Spence, Yun S. Song, Giovanni Poletti, Francois Balloux,
George van Driem(这哥儿们居然也在,呵呵), Peter de Knijff
et al.
AffiliationsContributionsCorresponding authors
Nature 538, 201–206 (13 October 2016) doi:10.1038/nature18964
Received 18 September 2015 Accepted 23 June 2016 Published online 21 September 2016

Abstract

Here we report the Simons Genome Diversity Project data set: high quality genomes from 300 individuals from 142 diverse populations. These genomes include at least 5.8 million base pairs that are not present in the human reference genome. Our analysis reveals key features of the landscape of human genome variation, including that the rate of accumulation of mutations has accelerated by about 5% in non-Africans compared to Africans since divergence. We show that the ancestors of some pairs of present-day human populations were substantially separated by 100,000 years ago, well before the archaeologically attested onset of behavioural modernity. We also demonstrate that indigenous Australians, New Guineans and Andamanese do not derive substantial ancestry from an early dispersal of modern humans; instead, their modern human ancestry is consistent with coming from the same source as that of other non-Africans.



物格而后知至,知至而后意诚,意诚而后心正,心正而后身修,身修而后家齐,家齐而后国治,国治而后天下平...
...因为原文需要购买,暂时下不到原文,只找到根据原文整理的丹人血统全球分布图A world map of Neanderthal and Denisovan ancestry in modern humans  https://phys.org/news/2016-03-wo ... ncestry-modern.html,如下:


imvivi001 发表于 2017-1-16 12:25
评论员根据采访作者得出的这幅图似乎有误,原图如下:
丹人基因-全球分布图-2.png
2017-1-17 06:55


Estimate ofDenisovan ancestry with a heatmap scale of 0–0.5% to bring outsubtle differences in mainlandEurasia (Oceanian groups with asmuch as 5% Denisovan ancestryare saturated in bright red)
物格而后知至,知至而后意诚,意诚而后心正,心正而后身修,身修而后家齐,家齐而后国治,国治而后天下平...
本帖最后由 一统浆糊 于 2017-1-17 07:06 编辑
29# 天天向上  
不知所云,只能说你嘴尖皮厚而已
baiyueren 发表于 2017-1-15 13:03
I do not think this is appropriate.
极品猥琐凤凰眼镜生物党棍左棍五毛愤青爱国
eight代 poor农 root正 shoot
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