一項(xiàng)對坦桑尼亞和南非狩獵采集人群的50多萬種遺傳標(biāo)記的研究顯示,博茨瓦納,、納米比亞和南非北部喀拉哈里沙漠地區(qū)的以咔噠聲作為語言的布須曼人擁有全世界最高的遺傳多樣性水平。Brenna M. Henn及其同事研究了27個非洲人群的遺傳標(biāo)記,,包括來自坦桑尼亞的哈扎人,、散達(dá)維人的以咔噠聲作為語言的個體和南非的Khomani布須曼人,。這組作者探索了這些人群的祖先世系,來確定非洲的狩獵-采集人群和農(nóng)業(yè)-游牧人群是否具有明顯不同的人口歷史,。他們的分析提示這些狩獵-采集人群擁有其他非洲人口沒有的遺傳多樣性,。這組作者發(fā)現(xiàn),在過去5000年中,,隨著農(nóng)業(yè)人群在非洲擴(kuò)展,,像哈扎人這樣的一些狩獵-采集者的人口規(guī)模急劇下降,而另外一些人群最近已經(jīng)開始吸收農(nóng)業(yè)移民,。這組作者說,,該研究發(fā)現(xiàn)的這種遺傳多樣性的模式提示,現(xiàn)代人起源于非洲南部,,而不是此前認(rèn)為的起源于東非,。(生物谷Bioon.com)
生物谷推薦原文出處:
PNAS doi: 10.1073/pnas.1017511108
Hunter-gatherer genomic diversity suggests a southern African origin for modern humans
Brenna M. Henna,1, Christopher R. Gignouxb, Matthew Jobinc,d, Julie M. Grankae, J. M. Macphersonf, Jeffrey M. Kidda, Laura Rodríguez-Botiguég, Sohini Ramachandranh, Lawrence Honf, Abra Brisbini, Alice A. Linj, Peter A. Underhillj, David Comasg, Kenneth K. Kiddk, Paul J. Normanl, Peter Parhaml, Carlos D. Bustamantea, Joanna L. Mountainf, and Marcus W. Feldmane
Africa is inferred to be the continent of origin for all modern human populations, but the details of human prehistory and evolution in Africa remain largely obscure owing to the complex histories of hundreds of distinct populations. We present data for more than 580,000 SNPs for several hunter-gatherer populations: the Hadza and Sandawe of Tanzania, and the ≠Khomani Bushmen of South Africa, including speakers of the nearly extinct N|u language. We find that African hunter-gatherer populations today remain highly differentiated, encompassing major components of variation that are not found in other African populations. Hunter-gatherer populations also tend to have the lowest levels of genome-wide linkage disequilibrium among 27 African populations. We analyzed geographic patterns of linkage disequilibrium and population differentiation, as measured by FST, in Africa. The observed patterns are consistent with an origin of modern humans in southern Africa rather than eastern Africa, as is generally assumed. Additionally, genetic variation in African hunter-gatherer populations has been significantly affected by interaction with farmers and herders over the past 5,000 y, through both severe population bottlenecks and sex-biased migration. However, African hunter-gatherer populations continue to maintain the highest levels of genetic diversity in the world.