%0 Case Reports
%T Low-level mosaic trisomy 17 at amniocentesis in a pregnancy associated with a favorable fetal outcome and cytogenetic discrepancy between cultured and uncultured amniocytes.
%A Chen CP
%A Chen SW
%A Chern SR
%A Chen YY
%A Wu FT
%A Pan YT
%A Lee CC
%A Pan CW
%A Wang W
%J Taiwan J Obstet Gynecol
%V 62
%N 2
%D Mar 2023
%M 36965908
%F 1.944
%R 10.1016/j.tjog.2022.12.005
%X <B>OBJECTIVE: </B>We present low-level mosaic trisomy 17 at amniocentesis in a pregnancy associated with a favorable fetal outcome and cytogenetic discrepancy between cultured and uncultured amniocytes.<BR><B>METHODS: </B>A 32-year-old, primigravid woman underwent amniocentesis at 18 weeks of gestation because of an increased nuchal translucency thickness of 3 mm in the first trimester sonographic screening. Amniocentesis revealed a karyotype of 47,XX,+17 [2]/46,XX [20]. Among 22 colonies of cultured amniocytes, two colonies had a karyotype of 47,XX,+17, whereas the rest 20 colonies had a karyotype of 46,XX. Simultaneous array comparative genomic hybridization (aCGH) on the DNA extracted from uncultured amniocytes revealed arr (1-22,X) × 2 with no genomic imbalance. Prenatal ultrasound and parental karyotypes were normal. Quantitative fluorescence polymerase chain reaction (QF-PCR) analysis on the DNA extracted from the parental bloods and cultured amniocytes excluded uniparental disomy (UPD) 17. The woman was encouraged to continue the pregnancy. A normal 3178-g female baby was delivered at 38 weeks of gestation without any phenotypic abnormalities. The karyotypes of cord blood, umbilical cord and placenta were all 46, XX (40/40 cells). When follow-up at age six months, the neonate was normal in physical and psychosomatic development.<BR><B>CONCLUSIONS: </B>Low-level mosaic trisomy 17 at amniocentesis can be a transient and benign condition, and can be associated with a favorable fetal outcome and cytogenetic discrepancy between cultured and uncultured amniocytes.