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染色体决定了男儿身。但是这并不意味着X染色体对男儿身没有影响。X染色体在精子的形成过程中起重要作用。
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染色体的进化,研究人员首先以前所未有的精确度排序人类染色体。然后他们对比了老鼠的染色体序列。老鼠从8000晚年前开始分化出来。
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.
结果人类跟老鼠的X染色体基因95%是重合的。这个发现并不意外。60年代的时候,生物学家Susumu Ohno提出X染色体进化缓慢,大多数哺乳动物的X染色体基因是相似的。但是随着时间的推移,确实有些区别。或者确切的说是144处不同。
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 Nature Genetics.
人类X染色体上有144组基因不同于老鼠。这些基因看起来是在持续发展。这些基因里的许多在女性体内都是静止的,只有涉及到精子产生的时候才活跃起来。研究发表在《自然遗传学》杂志上。
Clearly, the X chromosome Xceeds its feminine responsibilities. Which is Xcellent news for male fertility.
很明显,X染色体不光对雌性起作用。这对男性生育来说是个好消息。
—Sophie Bushwick