美國(guó)《自然》雜志網(wǎng)站1月13日刊發(fā)的一項(xiàng)研究報(bào)告顯示,，Y染色體是人類所有基因中演化最快的染色體。
據(jù)報(bào)道,，科學(xué)家通過(guò)將人類的基因與最像人類的“近親”猩猩相比對(duì),，發(fā)現(xiàn)Y染色體與猩猩的差異度為30%，而人類其它基因與猩猩的差異度為28%,，這也就是說(shuō)人類的Y染色體與人類其它基因相比存在2個(gè)百分點(diǎn)的進(jìn)化程度差異,。而這一演化過(guò)程是從大約600萬(wàn)年前開(kāi)始的,。
研究報(bào)告的撰寫(xiě)者,、劍橋大學(xué)懷特黑德研究所主任戴維·佩奇和麻省理工學(xué)院的一名教授表示：“看起來(lái)Y染色體是人類染色體中演化最快的一個(gè)，它幾乎就是一個(gè)不斷變化的基因,，就像是一座不斷重建的房屋一樣,。”
懷特黑德研究所的詹妮弗·休斯說(shuō)，研究人員對(duì)人類和猩猩的Y染色體進(jìn)行了詳細(xì)的比對(duì),，發(fā)現(xiàn)染色體的整個(gè)切片存在巨大的不同,，人類的Y染色體存在著完整的基因,，但猩猩的Y染色體上卻沒(méi)有。
當(dāng)然,，男人們也不要對(duì)這個(gè)消息太得意,。休斯提醒說(shuō)，決定人類性別的Y染色體演化的速度雖然很快,，但這并不意味著男人本身就進(jìn)化得更為高級(jí),。不過(guò)科學(xué)家表示，即便如此,，我們還是可以肯定地說(shuō),，Y染色體就是人類染色體演化速度的冠軍。（生物谷Bioon.com）
PLoS Genet：Y染色體或?qū)⒃谶M(jìn)化中消失
Nature：新性染色體進(jìn)化驅(qū)動(dòng)脊椎動(dòng)物新種形成
按照性情做科學(xué)--生物谷訪賽業(yè)生物科技首席科學(xué)顧問(wèn)藍(lán)田博士
生物谷推薦原始出處：
Nature advance online publication 13 January 2010 | doi:10.1038/nature08700
Chimpanzee and human Y chromosomes are remarkably divergent in structure and gene content
Jennifer F. Hughes1, Helen Skaletsky1, Tatyana Pyntikova1, Tina A. Graves2, Saskia K. M. van Daalen3, Patrick J. Minx2, Robert S. Fulton2, Sean D. McGrath2, Devin P. Locke2, Cynthia Friedman4, Barbara J. Trask4, Elaine R. Mardis2, Wesley C. Warren2, Sjoerd Repping3, Steve Rozen1, Richard K. Wilson2 & David C. Page1
1 Howard Hughes Medical Institute, Whitehead Institute, and Department of Biology, Massachusetts Institute of Technology, 9 Cambridge Center, Cambridge, Massachusetts 02142, USA
2 The Genome Center, Washington University School of Medicine, 4444 Forest Park Boulevard, St Louis, Missouri 63108, USA
3 Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Academic Medical Center, Amsterdam 1105 AZ, The Netherlands
4 Division of Human Biology, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue North C3-168, Seattle, Washington 98109, USA
The human Y chromosome began to evolve from an autosome hundreds of millions of years ago, acquiring a sex-determining function and undergoing a series of inversions that suppressed crossing over with the X chromosome1, 2. Little is known about the recent evolution of the Y chromosome because only the human Y chromosome has been fully sequenced. Prevailing theories hold that Y chromosomes evolve by gene loss, the pace of which slows over time, eventually leading to a paucity of genes, and stasis3, 4. These theories have been buttressed by partial sequence data from newly emergent plant and animal Y chromosomes5, 6, 7, 8, but they have not been tested in older, highly evolved Y chromosomes such as that of humans. Here we finished sequencing of the male-specific region of the Y chromosome (MSY) in our closest living relative, the chimpanzee, achieving levels of accuracy and completion previously reached for the human MSY. By comparing the MSYs of the two species we show that they differ radically in sequence structure and gene content, indicating rapid evolution during the past 6?million years. The chimpanzee MSY contains twice as many massive palindromes as the human MSY, yet it has lost large fractions of the MSY protein-coding genes and gene families present in the last common ancestor. We suggest that the extraordinary divergence of the chimpanzee and human MSYs was driven by four synergistic factors: the prominent role of the MSY in sperm production, ‘genetic hitchhiking’ effects in the absence of meiotic crossing over, frequent ectopic recombination within the MSY, and species differences in mating behaviour. Although genetic decay may be the principal dynamic in the evolution of newly emergent Y chromosomes, wholesale renovation is the paramount theme in the continuing evolution of chimpanzee, human and perhaps other older MSYs.
