Men Need X Chromosome to Make More Men (and Women)

Men Need X Chromosome to Make More Men (and Women)
男人需要X染色体才能造更多男人（以及女人）
It takes a Y chromosome to make a man. But that doesn't mean its counterpart, the X chromosome, plays no part. In fact, it has a big role in making sperm.
Y染色体会制造男人。担并不意味着X染色体不重要。实际上，它在制造精子时发挥很大的作用。
To study X evolution, researchers first sequenced the human chromosome more accurately than ever before. Then they compared the code to that of a mammal whose evolutionary lineage split from ours about 80 million years ago: the mouse.
为了研究X染色体的演化，研究人员更精确的测量了人类染色体的序列。然后和哺乳动物老鼠进行了比较。它们的演化族譜相距我们8000万年。
It turns out that humans and mice share 95 percent of their X genes. This finding was no surprise. In the 1960s, biologist Susumu Ohno suggested the X chromosome would evolve slowly, and thus remain similar in most mammalian species. But some things did change over evolutionary time. Or rather, 144 things.
One-hundred-forty-four human X chromosome genes had no counterparts in mice. And these genes seemed to be constantly developing. Many of the genes remained dormant in females, only becoming active in tissues involved in sperm production. The study is in the journal NatureGenetics. [Jacob L. Mueller et al., Independent specialization of the human and mouse X chromosomes for the male germ line]
结果发现，人和鼠的X基因有95%的相同。这并不令人惊讶。1960年代，生物学家Susumu Ohno 就提出，X染色体进化缓慢，因此在大部分哺乳动物中X染色体是相似的。但是有些东西在进化过程中确实改变了。直接来说，就是有144个改变。144个人类X染色体基因在老鼠基因里没有。这些基因似乎发展稳定。有些基因对女性是休眠的，只有在产生精子时会有作用。研究发表在NatureGenetics. [Jacob L. Mueller et al., Independent specialization of the human and mouse X chromosomes for the male germ line]
Clearly, the X chromosome Xceeds its feminine responsibilities. Which is Xcellent news for male fertility.
显然，X染色体超出女性的责任。这对于男性的生育来说是好消息。