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。

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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。

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If so, there could be a familial genetic disorder called fragile X, in which a certain portion of the X chromosome is abnormal.

如果有，那么你很可能有脆弱X基因的家族遗传病。也就是X基因的一部分是异常的。

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