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欧亚起源的mtDNA L3和Y-snp DE

Carriers of mitochondrial DNA macrohaplogroup L3 basic lineages migrated back to Africa from Asia around 70,000 years ago.
Abstract
Background: After three decades of mtDNA studies on human evolution the only incontrovertible main result is the African origin of all extant modern humans. In addition, a southern coastal route has been relentlessly imposed to explain the Eurasian colonization of these African pioneers. Based on the age of macrohaplogroup L3, from which all maternal Eurasian and the majority of African lineages originated, that out-of-Africa event has been dated around 60-70 kya. On the opposite side, we have proposed a northern route through Central Asia across the Levant for that expansion. Consistent with the fossil record, we have dated it around 125 kya. To help bridge differences between the molecular and fossil record ages, in this article we assess the possibility that mtDNA macrohaplogroup L3 matured in Eurasia and returned to Africa as basic L3 lineages around 70 kya. Results: The coalescence ages of all Eurasian (M,N) and African L3 lineages, both around 71 kya, are not significantly different. The oldest M and N Eurasian clades are found in southeastern Asia instead near of Africa as expected by the southern route hypothesis. The split of the Y-chromosome composite DE haplogroup is very similar to the age of mtDNA L3. A Eurasian origin and back migration to Africa has been proposed for the African Y-chromosome haplogroup E. Inside Africa, frequency distributions of maternal L3 and paternal E lineages are positively correlated. This correlation is not fully explained by geographic or ethnic affinities. It seems better to be the result of a joint and global replacement of the old autochthonous male and female African lineages by the new Eurasian incomers. Conclusions: These results are congruent with a model proposing an out-of-Africa of early anatomically modern humans around 125 kya. A return to Africa of Eurasian fully modern humans around 70 kya, and a second Eurasian global expansion by 60 kya. Climatic conditions and the presence of Neanderthals played key roles in these human movements.


https://www.biorxiv.org/content/early/2017/12/13/233502
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Figure 1. Geographic origin and dispersion of mtDNA L haplogroups
(a) Sequential expansion of L haplogroups inside Africa and exit of the L3 precursor to Eurasia.
a.jpg
2018-1-6 14:34
Figure 1. Geographic origin and dispersion of mtDNA L haplogroups
(b). Return to Africa and expansion to Asia of basic L3 lineages with subsequent differentiation in both continents.
b.jpg
2018-1-6 14:35
粗读了一下文章给出的假说。早一次出非洲的现代人从西亚到了中亚,其中有mtDNA单倍群L3*,伴随的有Y-单倍群DE。在7-10万年间的冰川期,一部分人向西南回到了非洲,其中有Y-单倍群有E,另一部分人向东南到了东南亚,其中有Y-单倍群有D。
我的观点与此文类似:

Chinese Science Bulletin. 2017, 62(5):316-318.

Fuyan human of 120-80 kya cannot challenge the Out-of-Africa theory for modern human dispersal

Wei Lanhai, Li Hui
1

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人类之子全都是为死而生。
              --------《阙特勤碑》
Skeletal remains unearthed in
71 the Skhul and Qafzeh caves demonstrated that early modern
72 humans were present in the Levant between 125 and 80 kya [10].
73 The discovery of modern human teeth in southern China dated to
74 120-80 kya [11], also supports the presence of anatomically modern
75 humans (AMHS) in eastern Asia during this period. Several
76 archaeological studies uncovered Middle Stone Age (MSA) lithic
77 assemblages, dated around 125-75 kya, in different regions of the
78 Arabian Peninsula, presenting affinities with northeastern African
79 assemblages of the same period [12–14]. These findings suggest
80 that African AMHS may have extended its geographic range to
81 eastern and northern Arabia long before the time frame proposed by
82 molecular data.  [16]

the Neanderthal introgression into modern humans in
85 Europe has been dated within 35-65 kya [15] which is well in frame
86 with the molecular clock window established for the African exit of
87 modern humans
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...
我的观点与此文类似:

Chinese Science Bulletin. 2017, 62(5):316-318.

Fuyan human of 120-80 kya cannot challenge the Out-of-Africa theory for modern human dispersal

Wei Lanhai, Li Hui
Ryan 发表于 2018-1-6 18:21
颇有道理!
如果可以检测出湖南福岩洞古人或以色列Qafzeh洞古人的DNA那就精彩了~
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...
粗读了一下文章给出的假说。早一次出非洲的现代人从西亚到了中亚,其中有mtDNA单倍群L3*,伴随的有Y-单倍群DE。在7-10万年间的冰川期,一部分人向西南回到了非洲,其中有Y-单倍群有E,另一部分人向东南到了东南亚,其 ...
cpan0256 发表于 2018-1-6 16:07
粗读了一下,感觉这个西班牙团队的新假说难以成立,因为 :1、无法解释某些L3*富集于非洲而不是亚洲;2、如果L3*真的如作者推测,以南亚为中心向东西两个方向扩散,那么以L3+yE在非洲占据的优势,则无法解释为何非洲土著的常染色体方面亚洲血统如此之少,且不论为何几乎没有尼人血统。

是的,正如我之前说过的,在7万年‘非洲智人’的亚欧大扩散之前,就必定存在非洲人群或彼时的东非人群或亚非交界处人群向亚欧大陆的扩散(这个多项研究已经证实,其中包括兰版的最新论文),不过影响力是极其有限的。而托岜湖超级大爆发之后的扩散,才真正奠基了现代亚欧人群的主体,当然是与亚欧土著混合的结果。
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...
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