据统计，近亲结婚所生的子女，遗传病的发病率比非近亲结婚高150倍，婴儿死亡率高3倍多，20周岁前的死亡率高8倍。1981年，我国开始施行的新《婚姻法》规定：“禁止直系血亲和三代以内的套系血亲结婚。”这对少年儿童的健康成长、提高人类的素质有极其重要的作用，也是历史发展 According to statistics, children born of cousins, genetic disease incidence 150 times higher than non-relatives marriages, infant mortality rate more than 3 times, 20 years old before the high mortality rate 8 times. In 1981, the new “Marriage Law” put into effect in our country stipulated: “Forbidding direct blood relatives and marrying relatives within three generations shall not be marred.” This plays an extremely important role in the healthy growth of children and the enhancement of human qualifications and is also a historical development