人类染色体异常包括数目和结构异常.至今世界上已报道的染色体数目异常和结构畸变有2万余种,其中包括我国所报道的729种。通过对流产、死产及新生儿和一般人群的调查表明,染色体异常占流产胚胎的60％,占死产婴的8‰,占新生儿死亡者的6‰,占新生活婴的10‰,占一般人群的5‰;在一般人群中,平衡易位占1.9‰(其中约有15％生育力降低),不平衡易位占0.5‰.不平衡易位通常引 There are more than 20,000 chromosome abnormalities and structural aberrations in the world, including 729 species reported in our country. A survey of miscarriage, stillbirth, newborns and the general population showed that chromosomal abnormalities account for 60% of abortions, 8 ‰ of stillbirths, 6 ‰ of newborn babies, 10 ‰ of newborn babies, Accounting for 5 ‰ of the general population; in the general population, the balance of translocations accounted for 1.9 ‰ (of which about 15% decreased fertility), unbalanced translocation accounted for 0.5 ‰.