国际生殖健康/计划生育杂志2024,Vol.43Issue(4):305-308,327,5.DOI:10.12280/gjszjk.20240067
表型正常母亲二次孕育21-三体综合征患儿的遗传学分析
Genetic Analysis of Second Pregnancy with A Child of 21-Trisomy Syndrome in A Phenotypically Normal Mother
摘要
Abstract
The repeated pregnancies with 21-trisomy syndrome in a phenotypically normal mother are rare,and the possibility of maternal chromosomal mosaic should be considered.We report a woman with normal phenotype who had a history of early embryo loss for 4 times,two of which the karyotypes were 47,XY,+21.The couple's karyotypes were normal(counting 20 split phases).Both noninvasive prenatal testing(NIPT)and extended NIPT results refer to a high risk of trisomy 21,and the amniocentesis single nucleotide polymorphism array(SNP-array)result was[arr(1-22)×2,(XN×1)],and the fetal amniotic fluid karyotype was 46,XN.The repeated peripheral blood chromosomes test for the couple(counting 50 split phases)was performed,the maternal chromosome karyotype was diagnosed as 47,XX,+21[4]/46,XX[46],with a mosaic ratio of 7%-8%.Maternal fluorescence in situ hybridization(FISH)assay in 100 counted cells showed 7 trisomy 21 cells,suggesting that 7%of the cells were trisomy 21.Fetal amniotic fluid FISH test found no 21-trisomy cell.A healthy baby girl was delivered by cesarean section at 40+1 weeks of gestation.In this case,maternal karyotype of a mosaic 21-trisomy cell/normal cell phenotype may contribute to the twice early pregnancy losses with 21-trisomy syndrome.关键词
唐氏综合征/三体性/嵌合体/遗传咨询/核型分析/原位杂交,荧光Key words
Down syndrome/Trisomy/Chimera/Genetic counseling/Karyotyping/In situ hybridization,fluorescence引用本文复制引用
刘国忠,侯海燕,常玉,郝春霞,睢丽婷..表型正常母亲二次孕育21-三体综合征患儿的遗传学分析[J].国际生殖健康/计划生育杂志,2024,43(4):305-308,327,5.基金项目
国家自然科学基金(81402691) (81402691)