一例无创产前检测辅助报告X染色体异常的羊水细胞遗传学分析  

Cytogenetic analysis of an amniotic sample with X chromosome abnormality signaled by non-invasive prenatal testing

作　　者：章卫国[1] 张蔚卿[1] 潘飞燕[1] 王冬英 Zhang Weiguo;Zhang Weiqing;Pan Feiyan;Wang Dongying(Taizhou Hospital of Zhejiang Province,Taizhou,Zhejiang 317000,China;Yiwu Maternal and Child Health Care Hospital,Yiwu,Zhejiang 322000,China)

机构地区：[1]浙江省台州医院,317000 [2]浙江省义乌市妇幼保健院,322000

出　　处：《中华医学遗传学杂志》2021年第6期573-576,共4页Chinese Journal of Medical Genetics

基　　金：浙江省医药卫生科技计划(2021KY1196);台州市科技计划(20ywa13);台州恩泽医疗中心(集团)科研基金(19EZD44)。

摘　　要：目的探讨1例无创产前检测(non-invasive prenatal testing,NIPT)辅助报告提示X染色体基因组拷贝数变异(copy number variation,CNV)胎儿的染色体核型。方法采集孕妇的羊水及脐血样本,常规进行G显带染色体分析,用高通量测序检测染色体微缺失/微重复,之后对分裂中期细胞进行荧光原位杂交(fluorescence in situ hybridization,FISH)验证。结果孕妇NIPT检测提示21-三体、18-三体、13-三体低风险,但辅助报告提示X染色体数目偏少(45,X)。羊水及脐血细胞染色体核型为46,XX,高通量测序结果为seq[hg19](X)×1,(Y)×2;FISH结果为46,X,ish idic(Y)(q11.23)(SRY++,DXZ1+);C显带Y染色体两端可见一深染致密和一浅染疏松的着丝粒,异染色质区缺失。胎儿的核型最终被确定为46,X,pus idic(Y)(q11.23)。结论对NIPT辅助报告提示的异常,应采取染色体核型分析结合高通量测序进行确诊,以避免染色体微缺失/微重复综合征患儿的出生。Objective To determine the chromosomal karyotype of a fetus with copy number variation(CNV)of the X chromosome signaled by non-invasive prenatal testing(NIPT).Methods NIPT was performed on the peripheral blood sample taken from the pregnant women.Amniotic fluid and cord blood samples were subjected to conventional G banded karyotyping,and were further analyzed by high-throughput sequencing for chromosome microdeletion/microduplication.The results were then verified by fluorescence in situ hybridization(FISH)on metaphase cells.Results The NIPT test of pregnant women suggested low risk for 21-trisomy,18-trisomy,and 13-trisomy,whilst indicated the number of chromosome X to be low.The G banded karyotype of the amniotic fluid and cord blood cells was 46,XX.The result of high-throughput sequencing chromosome microdeletion/microduplication detection was seq[hg19](X)×1,(Y)×2.FISH showed a clear red signal at each end of a whole chromosome,and a green signal on the other chromosome,with a karyotype of 46,X,ish idic(Y)(q11.23)(SRY++,DXZ1+).C banding showed that there is a dense and a slightly loose centromere at both ends of the Y chromosome,and the parachromatin region was missing.The karyotype of amniotic fluid and cord blood cells was finally determined to be 46,X,pus idic(Y)(q11.23).Conclusion For chromosome anomalies suggested by auxiliary report of NIPT,conventional karyotyping combined with high-throughput sequencing for chromosome microdeletion/microduplication should be adopted for the prevention and reduction of the rate of chromosome microdeletion/microduplication syndromes.

关 键 词：无创产前检测 拷贝数变异 染色体微缺失/微重复 荧光原位杂交 

分 类 号：R714.5[医药卫生—妇产科学]