直立行走是人類區(qū)別于猿類的重要特征，同時,，現(xiàn)代人類也具有很高的表型多樣性,。這些形態(tài)的差異很大部分是由骨骼系統(tǒng)塑造而成的。例如不同人群在體型,、骨密度,、臉型等等方面都表現(xiàn)出巨大差異。但是,，關(guān)于現(xiàn)代人類骨骼系統(tǒng)快速進化和相應(yīng)的形態(tài)多樣性形成的遺傳機制目前尚不得而知,。
為了揭開人類表型多樣性的奧妙，中國科學院昆明動物研究所博士研究生吳東東與導師張亞平院士系統(tǒng)分析了骨骼發(fā)育相關(guān)基因群的群體多態(tài)性,，并與基因組中的其它基因進行比較,，發(fā)現(xiàn)骨骼基因中的SNP位點在非洲人群和非非洲人群(東亞和歐洲人群)之間表現(xiàn)出很高的群體分化特征。值得注意的是,，這一特點在可能影響基因功能的非同義替代突變中尤為突出,，但東亞和歐洲人群之間并沒有表現(xiàn)出此現(xiàn)象。有趣的是,，骨骼基因中的高分化SNP在東亞人群和歐洲人群具有很高的衍生等位基因頻率,，但非洲人群中卻沒有。
他們的研究結(jié)果表明,，很可能在人類走出非洲之后,，骨骼基因在達爾文正選擇作用的驅(qū)動下出現(xiàn)了功能變化，導致了人類骨骼系統(tǒng)的快速進化和相應(yīng)的形態(tài)分化,，以適應(yīng)走出非洲后面臨的新環(huán)境。他們的成果為了解現(xiàn)代人類形態(tài)分化的機制提供了重要線索,。
國際著名刊物Human Molecular Genetics雜志在線發(fā)表了該研究成果,。(生物谷Bioon.com)
最大規(guī)模人類遺傳多樣性調(diào)查完成
Nature：脊索動物在進化中地位的重新評估
Nature：早期類人猿的進化及分類
Nature：蛋白質(zhì)進化難以逆轉(zhuǎn)
生物谷推薦原文出處：
Human Molecular Genetics doi:10.1093/hmg/ddq107
Positive selection drives population differentiation in the skeletal genes in modern humans
Dong-Dong Wu1,3 and Ya-Ping Zhang1,2,*
1 State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China; 2 Laboratory for Conservation and Utilization of Bio-resources, Yunnan University, Kunming 650091, China; 3 Graduate School of the Chinese Academy of Sciences, Beijing, China;
During the course of evolution, the human skeletal system has evolved rapidly leading to an incredible array of phenotypic diversity, including variations in height and bone mineral density. However, the genetic basis of this phenotypic diversity and the relatively rapid tempo of evolution have remained largely undocumented. Here, we discover that skeletal genes exhibit a significantly greater level of population differentiation among humans compared with other genes in the genome. The pattern is exceptionally evident at amino acid-altering sites within these genes. Divergence is greater between Africans and both Europeans and East Asians. In contrast, relatively weak differentiation is observed between Europeans and East Asians. SNPs with higher levels of differentiation have correspondingly higher derived allele frequencies in Europeans and East Asians. Thus, it appears that positive selection has operated on skeletal genes in the non-African populations and this may have been initiated with the human colonization of Eurasia. In conclusion, we provide genetic evidence supporting the rapid evolution of the human skeletal system and the associated diversity of phenotypes.
