Now some of these [disease genes] may be on the X chromosome, [meaning that women who have the second X chromosome with which to compensate, would have an advantage].

现在猜测这些疾病基因可能在X染色体上面，这意味着女性有着第二条基因去抵消的优势。

youdao

Fragile X syndrome, a single genetic mutation on the X chromosome, is the most common source of inherited mental impairment, affecting one in every 4,000 boys and one in every 6,000 girls.

脆性X综合征，一个X染色体上的基因突变，是遗传性智力障碍最常见的来源，每4000名男孩和每6000名女孩中就有一名儿童患有该症。

youdao

Fragile X syndrome, a single genetic mutation on the X chromosome, is the most common source of inherited mental impairment, affecting one in every 4, 000 boys and one in every 6, 000 girls.

脆性X综合征，一个X染色体上的基因突变，是遗传性智力障碍最常见的来源，每4000名男孩和每6000名女孩中就有一名儿童患有该症。

youdao

This is because, if you have very good intelligence genes on your X chromosome, it pays not to have them muffled by more average genes on another X chromosome.

BBC: NEWS | Science/Nature | Female chromosome has X factor

Your mother can give you only an X chromosome, but your father can pass on an X or a Y chromosome.

CNN: Triple X syndrome

Females with triple X syndrome have a third X chromosome.

CNN: Triple X syndrome