Women with one mutated gene copy have a remaining healthy copy, so they don’t get hemophilia unless X-chromosome inactivation turns off the normal copy in the majority of cells.

携带一个突的女性还有一个健康的拷贝，所以她们一般不会患血友病，除X染色体失使得大多数细胞中正常的拷贝沉默。

Now if this inactivation’s random, you’d expect about half of the female’s cells to have a functional dystrophin gene and the other half to have a defective dystrophin gene, and these people are typically asymptomatic.

如果失机的，可以预料到女性一半的细胞中抗肌萎缩蛋白正常的，另一半有缺陷的，通常这些人无临床症状。