自Lejeune1959年报道在先天性愚型病人的体细胞中观察到多了一条G组染色体以来,至今已发现染色体异常(包括数量畸变和结构畸变)所引起的染色体病多达三百种以上。用常规染色体分析查明,新生儿中染色体异常的发生率约为1％,其中约50％左右具有家族性,由于染色体异常除导致多种先天性缺陷外,常伴有智力低下和生长迟缓,给家庭、社会造成严重的精神和经济负担。因此,细胞遗传学工作 Since Lejeune’s report in 1959 that there has been a total number of G Group chromosomes in the genotypes of beneficiaries during the first days, more than 300 chromosomal diseases have been found to have been caused by chromosomal abnormalities (including quantitative and structural aberrations). With conventional chromosome analysis found that the incidence of chromosomal abnormalities in neonates is about 1%, of which about 50% have familial, in addition to leading to a variety of congenital defects in chromosomal abnormalities, often accompanied by mental retardation and growth retardation, To the family, the community caused a serious mental and financial burden. Therefore, cytogenetics work