Abstract: 【Objective】 To investigate the types and proportion of chromosomal abnormalities in patients with neurological dysplasia and pregnant women under 30 years old. 【Method】 329 cases,who were diagnosed neurological dysplasia and mother reproductive age less than 30 years old,were performed by karyotype analysis of peripheral blood. 【Results】 Among 329 cases,245 cases were found abnormal karyotype ( 74.5% ) .The percentage of euchromosome abnormalities was 85% (208 cases),including 190 cases of number abnormalities (190/245,36.7% ) and 18 cases of structure abnormalities (18/245,7.35% )from which 184 cases were Down syndrom,6 cases were 22 trisomy,the abnormal rate of boys was much higher than that of girls,boys∶girls=2.06∶1 .The percentage of sex chromosome abnormalities was 15 % ( 37 cases),including 9 cases of number abnormalities (9/245,3.67 % ),28 cases of structure abnormalities (28/245,11.4%);Of which the most common karyotype was fragil X syndrome,total 28 cases.Klinefelter syndrome was the common number abnormalities,karyotype 47,XXY( 4 cases);the main aneuploid forms of sex chromosome were 47,XYY(3 cases ),47,XXX(1 case ),49,XXXY(1 case ). 【Conclusion】 Down syndrome is still a common chromosomal abnormality among pregnant women under 30 years old.

Key words: chromosomal abnormality, abnormal karyotype, neurological dysplasia, children

摘要： 【目的】 分析30岁以下生育妇女子代神经发育障碍染色体核型异常的类型与比例。 【方法】 对临床医生诊断神经发育障碍并怀疑染色体异常的329例,母亲生育年龄30岁以下的患儿进行细胞遗传学检查。 【结果】 329例患儿中,检出染色体异常核型245例,异常率为74.5%。其中常染色体数目异常190例 (男∶女=2.06∶1),结构异常18例;性染色体异常共37例(15%),结构异常28例,数目异常9例。常染色体异常中最常见的是三体综合症,其中21三体综合症184例,占常染色体异常75.1%,22三体综合症6例。性染色体异常核型中最常见是脆X综合症,共28例,占性染色体异常75.5%。 【结论】 30岁以下生育妇女子代神经发育障碍常见染色体核型异常仍然是唐氏综合征。

关键词: 染色体核型分析, 神经发育异常, 年轻孕妇, 儿童