Because the hairs were incomplete, the type of testing, called mitochondrial DNA, can trace only the maternal line.

因为头发不完整，线粒体d NA检测的类型，只能追踪母系血统。

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Hemophilia is caused by a mutation—likely spontaneous in Victoria‘s case—on the X chromosome and can be passed along the maternal line of families.

血友病源于X染色体上的一种突变——很可能是维多利亚女皇自身发生的一种突变，可经由遗传系统传给家族后代。

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Although the culture of Mosuo was impacted by other ethnic groups for several times in the history, its maternal line culture has been successfully maintained.

摩梭文化在历史上曾多次受到其他民族文化的洗礼，但其母系文化仍以强有力的生命力在传承。

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