Roberts Eileen, Dunlop J, Davis G S, Churchill D, Davison E V
Regional Genetics Laboratories, Birmingham Women's Hospital NHS Trust, Edgbaston, Birmingham B15 2TG, UK.
Prenat Diagn. 2003 Jul;23(7):564-5. doi: 10.1002/pd.644.
To add to the knowledge base concerning confined placental mosaicism for trisomy 2.
Cytogenetic study of a late CVS referred for hyperechogenic bowel and raised AFP, and cytogenetic and molecular genetic study of a follow-up amniocentesis. Ultrasound monitoring at regular intervals following the CVS result.
All cells examined from direct and cultured CVS showed a 47,XY,+2 karyotype. Amniocentesis showed a mosaic 47,XY,+2[8]/46,XY[81] karyotype. Uniparental disomy (UPD) studies on the amniotic fluid showed normal biparental inheritance. The pregnancy developed oligohydramnios and IUGR and resulted in a 26-week liveborn male infant with a 46,XY karyotype, which died after 3 days because of complications of severe prematurity. Placental villi post delivery showed only the 47,XY,+2 cell line.
This case represents a further example of confined placental mosaicism (CPM) for trisomy 2 associated with oligohydramnios, IUGR and poor pregnancy outcome.
增加关于21三体局限型胎盘嵌合体的知识库。
对因肠回声增强和甲胎蛋白升高而转诊的晚期绒毛取样（CVS）进行细胞遗传学研究，并对后续羊膜穿刺术进行细胞遗传学和分子遗传学研究。根据绒毛取样结果定期进行超声监测。
直接采集和培养的绒毛取样所检测的所有细胞均显示为47,XY,+2核型。羊膜穿刺术显示为47,XY,+2[8]/46,XY[81]嵌合核型。对羊水进行的单亲二体（UPD）研究显示双亲遗传正常。妊娠出现羊水过少和胎儿宫内生长受限（IUGR），并产下一名26周的活产男婴，其核型为46,XY，该男婴因严重早产并发症在3天后死亡。产后胎盘绒毛仅显示47,XY,+2细胞系。
该病例是21三体局限型胎盘嵌合体（CPM）与羊水过少、胎儿宫内生长受限及不良妊娠结局相关的又一实例。
