Significance of mosaic isochromosome 20q on amniocentesis.
We report on 2 fetuses with prenatally diagnosed mosaic isochromosome 20q in amniotic fluid. Neither had an identifiable cytogenetic abnormality after birth. One infant developed a benign intracranial dermoid cyst at age 8 months. The other was completely normal in all respects. We are aware of 13 fetuses with this prenatally diagnosed chromosome finding; all fetuses tested have had normal chromosomes on subsequent cytogenetic studies and all, except one, have been morphologically normal. Fetuses with mosaic isochromosome 20q identified on amniocentesis are most likely to be phenotypically and cytogenetically normal after birth.
Donnenfeld
A E
AE
Department of Obstetrics and Gynecology, Pennsylvania Hospital, Philadelphia 19107.
Kershner
M A
MA
D000328:Adult; D000649:Amniocentesis; D002869:Chromosome Aberrations; D002890:Chromosomes, Human, Pair 20; D005260:Female; D006801:Humans; D007223:Infant; D009030:Mosaicism / Q000235:genetics*