Mosaic and hypermodal cells in amniotic fluid cell cultures.
Karyotypic results from a series of 975 consecutive amniotic fluid specimens studied for prenatal diagnosis are reported. In only 32% of specimens were all cells analyzed euploid. Two thirds (63%) of the specimens studied were hypomodal in at least one cell; 25% of the studies were hypomodal in three or more cells. In contrast, only 3.5% of the studies were hypermoidal in one or more cells. Most frequently an additional chromosome 2 was present in these hypermodal cells. Cells with other than a diploid chromosome constitution may be mistakenly identified as evidence of mosaicism. This is especially likely when the involved chromosome is one associated with a clinically defined syndrome.
D000653:Amniotic Fluid / Q000166:cytology*; D000782:Aneuploidy; D002478:Cells, Cultured; D002869:Chromosome Aberrations; D005260:Female; D006801:Humans; D007621:Karyotyping; D009030:Mosaicism; D011003:Ploidies; D011247:Pregnancy