there was a trace of consanguineous marriage in their marriages. some of them got married with chinese.
他们的婚姻既有其内部近亲结婚的迹象,也有与华人联姻的。
it is a recessive hereditary disease of autosome to be deaf and dumb. it was analysed through heredity that reducing or preventing consanguineous marriage can reduce the deaf-mute's birth rate.