染色体微阵列诊断胎儿18p11.32缺失合并18p11.2

Chromosomal microarray diagnosis of fetal 18P11.32 deletion with 18P11.2 duplication

目的产前诊断一例胎儿羊水细胞染色体核型结果为46,XN,del(18)(p11.2)?,利用染色体微阵列技术(chromosomal microarray analysis,CMA)进一步分析及验证。方法胎儿羊水行染色体G显带核型分析,并进行CMA检测验证核型分析的结果。结果胎儿羊水染色体320条带下结果为46,XN,del(18)(p11.2)?。Affymetrix CytoScan 750K Array染色体微阵列技术结果为:arr[hg19]18p11.32(136,227-2,548,101)x1;arr[hg19]18p11.32p11.21(2,548,667-15,170,636)x3;显示胎儿18号染色体18p11.32区段存在2.4 Mb片段的缺失,同时,18 p11.32p11.21区段存在12.6Mb片段的重复。结论 CMA技术可以精确定位断裂点,定位到常规G显带无法定位的胎儿18p部分单体,以及鉴别常规G显带无法查出的胎儿18p部分三体,在胎儿期诊断出可疑致病基因并分析表型与基因型的关系。

Objective:To analyze and diagnosis the chromosome karyotype of a case of fetal amniotic cell results were as follows:46,XN,del(18)(p11.2)?,Chromosomal microarray analysis(CMA)was used for development and verify the source.Methods:The fetus’ s chromosome was analyzed and verified using karyotype analysis and CMA.Results:G-binding analysis showed a chromosome karyotype of 46,XN,del(18)(p11.2)?.The Affymetrix CytoScan 750K Array CMA analysis detected a 2.4Mb chromosome fragment deletion of 18p11.32(arr[hg19]18p11.32(136,227-2,548,101)x1),and a 12.6Mb chromosome fragment duplication of 18p11.32p11.21(arr[hg19]18p11.32p11.21(2,548,667-15,170,636)x3).Conclusion:CMA technology can accurately locate the fracture point,Locating the 18p partial monomer that could not be located by conventional G banding.And to identify 18p partial trisomy,the short arm of fetal chromosome 18,which cannot be detected by normal G banding.Diagnosis of suspicious pathogenic genes during fetal period and analysis of the relationship between phenotype and genotype.