Antenatal diagnosis of mosaic trisomy 8 confirmed in fetal tissues

An aneuploid karyotype with an extra submetacentric C-group chromosome was observed in all metaphase cells in 5 of 24 primary amniotic fluid cell clones and in admixture with normal cells in two additional clones. Trisomy 8 was demonstrated by R-banding. The parents elected to terminate the pregnancy. Successful cultures were initiated from nine fetal tissues and aneuploid cells were observed in cultures derived from two separate sites in the skin.