2月23日，學術期刊Nature上刊登了一項研究成果稱，近期對于恒河猴進行的一項研究顯示，社會上盛傳的所謂Y染色體將逐漸消失，并zui終導致雄性滅亡的傳聞并非事實。雄性DNA在早期確實經歷過迅速的衰落，但是這一趨勢已經被遏制。
研究人員表示他們希望這一發現將終結這一有關雄性染色體危機的謠言。這一謠言聲稱在過去3億年內，Y染色體已經從1400組基因下降為今天的僅有45組。這種理論被稱作“腐爛的Y染色體”，這一理論認為Y染色體將不斷縮減直至消亡。
研究人員表示他們希望這一發現將終結這一有關雄性染色體危機的謠言。這一謠言聲稱在過去3億年內，Y染色體已經從1400組基因下降為今天的僅有45組
研究人員此次考察了恒河猴的基因演化情況，發現它們僅保留下了其祖先大約3%的常染色體。而在染色體更古老的位置上，在過去的2500萬年內則未丟失任何一組基因。
美國懷特海德生物醫藥研究所生物學教授大衛·佩吉（David Page）說：“在過去10年間，流行的一種觀點就是認為Y染色體正在消失。拋開這種說法是否有其堅實的科學基礎不說，這種說法的傳播速度之快令人驚訝，并且人們都深信不疑。”
他說：“幾乎人人都來向我求證這個問題。這個想法實在太有說服力，它甚至阻礙了我們去探究有關Y染色體的實質性問題。在歷史的早期，Y染色體確實經歷過高速的基因喪失，速度極快。但隨后這一速度就減緩了，這一趨勢現在仍在持續。”
研究人員們表示Y染色體的演化總的來說就是從一開始的急劇衰落過渡到之后的嚴格保護。
實驗室研究員詹妮弗·休斯（Jennifer Hughes）的早期工作證明了人類男性的Y染色體在過去600萬年內一直保持了穩定。她說：“我們一直致力于開發一種明確的方式來揭開Y染色體頭上籠罩著的神秘面紗。”
她說：“現在，我們的經驗數據向這一傳統的流行觀念提出了挑戰。恒河猴的雄性Y染色體和人類男性的Y染色體都沒有出現丟失情況，很顯然Y染色體并不會消失。”佩吉教授補充道：“這篇論文粉碎了有關Y染色體將消失的謠言。有了我們的這些數據，我認為任何人都無法否認這一事實。”（生物谷 ）
doi:10.1038/nature10843
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PMID:
Strict evolutionary conservation followed rapid gene loss on human and rhesus Y chromosomes
Jennifer F. Hughes, Helen Skaletsky, Laura G. Brown, Tatyana Pyntikova, Tina Graves, Robert S. Fulton, Shannon Dugan, Yan Ding, Christian J. Buhay, Colin Kremitzki, Qiaoyan Wang, Hua Shen, Michael Holder, Donna Villasana, Lynne V. Nazareth, Andrew Cree, Laura Courtney, Joelle Veizer, Holland Kotkiewicz, Ting-Jan Cho, Natalia Koutseva, Steve Rozen, Donna M. Muzny, Wesley C. Warren, Richard A. Gibbs,
The human X and Y chromosomes evolved from an ordinary pair of autosomes during the past 200–300 million years. The human MSY （male-specific region of Y chromosome） retains only three percent of the ancestral autosomes’ genes owing to genetic decay. This evolutionary decay was driven by a series of five ‘stratification’ events. Each event suppressed X–Y crossing over within a chromosome segment or ‘stratum’, incorporated that segment into the MSY and subjected its genes to the erosive forces that attend the absence of crossing over. The last of these events occurred 30 million years ago, 5 million years before the human and Old World monkey lineages diverged. Although speculation abounds regarding ongoing decay and looming extinction of the human Y chromosome, remarkably little is known about how many MSY genes were lost in the human lineage in the 25 million years that have followed its separation from the Old World monkey lineage. To investigate this question, we sequenced the MSY of the rhesus macaque, an Old World monkey, and compared it to the human MSY. We discovered that during the last 25 million years MSY gene loss in the human lineage was limited to the youngest stratum （stratum 5）, which comprises three percent of the human MSY. In the older strata, which collectively comprise the bulk of the human MSY, gene loss evidently ceased more than 25 million years ago. Likewise, the rhesus MSY has not lost any older genes （from strata 1–4） during the past 25 million years, despite its major structural differences to the human MSY. The rhesus MSY is simpler, with few amplified gene families or palindromes that might enable intrachromosomal recombination and repair. We present an empirical reconstruction of human MSY evolution in which each stratum transitioned from rapid, exponential loss of ancestral genes to strict conservation through purifying selection.
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