15500例新生儿脐带血染色体核型分析

Karyotype analysis of umbilical blood in 15 500 newborns

目的 研究新生儿脐带血中染色体异常的发生率,并对脐带血染色体数目与结构异常及染色体多态性进行综合分析。方法 对新生儿脐带血进行收集,进行淋巴细胞培养,常规G显带,行染色体核型分析。结果 在培养成功的15 500例脐带血标本中,检出异常核型314例,在人群中的发生率为2.03%;其中染色体倒位患儿220例,发生率1.42%,构成比70.10%;染体易位患儿41例,发生率0.26%,构成比13.00%;染色体衍生患儿14例,发生率0.09%,构成比4.51%;21-三体患儿12例,发生率0.08%,构成比3.80%;D-G组易位患儿11例,发生率0.08%,构成比3.50%;性染色体异常中47,XXX患儿5例,47,XXY患儿7例,45,X患儿4例,发生率0.10%,构成比5.10%。染色体多态性检出317例,其发生率为2.04%。其他各组与倒位组发生率及构成比比较,均差异有统计学意义（χ^2=11.53,15.98;P〈0.05）;而易位、衍生、21-三体、D-G组易位及性染色体异常等发生率比较,差异无统计学意义（P〉0.05）,各组异常自然发生率比较接近。结论 新生儿脐带血染色体核型分析,对目前产前诊断不足具有很好的补充意义,对二级预防、再生育及临床指导有重要意义。

Objective To study the incidence of chromosomal abnormalities in the umbilical cord blood,and analyze the number and structure and chromosome poly-morphism of the cord blood. Methods Umbilical cord blood was collected for lymphocyte culture, conventional G-banding and karyotype analysis. Results 15 500 cases of umbilical cord blood samples were detected, of which 314 cases were abnormal karyotypes,the rate was 2.03%.Chromosomal inversions of children were 220,the percentage in population was 1.42%,the constituent ratio was 70.10%.Chromosomal translocations samples were 41,the percentage in population was 0.26%,the constituent ratio was 13.00%.Chromosome-derived samples were 14,the percentage in population was 0.09%,the constituent ratio was 4.51%.Children with 21-Down Syndrome samples were 12,the percentage in population was 0. 08%, the constituent ratio was 3.80%. Children with displaced robertson were 11, the percentage in population was 0.08%, the constituent ratio was 3. 50%. In sex chromosome abnormalities,47,XXX were 5,47,XXY were 7,45,X were 4,the percentage in population was 0.10%,the constituent ratio was 5.10%.Children with chromosomal polymorphism were 317,the percentage in population was 2. 04%. Compared with the other groups, the chromosomal inversions group′ proportion and constituent ratio were significantly different （ χ^2 = 11. 53, 15. 98; P 〈0. 05 ） . The differences among translocateon,chromosome-derived,21-Down Syndrome,D-G group and sex chromosome abnormal incidence＆amp;nbsp;were not significant （ P 〉0.05）,the incidence of abnormal natural of each group was closer.Conclusions Karyotype analysis of neonatal umbilical cord blood is a very useful to the insufficient prenatal diagnosis,and important for secondary prevention,fertility and clinical guidlines.