Rapid prenatal diagnosis of GM1-gangliosidosis using microchemical methods.

Prenatal diagnoses were established in 3 pregnancies at risk for GM1-gangliosidosis at 9, 10, and 12 days after amniocentesis. Beta-galactosidase activities in cultured amniotic fluid cells were determined by microchemical assays in cell homogenates and in isolated groups of 10--30 freeze-dried cells. The latter method requires only a few hundred cells growing in one or more clones and will usually allow a diagnosis within 9--12 days after amniocentesis.