Prenatal diagnosis of GM1-gangliosidosis: biochemical manifestations in fetal tissues.

A prenatal diagnosis of GM1-gangliosidosis was made in a pregnancy at risk, on the basis of a deficiency of beta-galactosidase activity demonstrated in cultured amniotic fluid cells. Biochemical analyses were performed in the aborted fetus. GM1-ganglioside beta-galactosidase activity was reduced to 1% of the control value in both the brain and liver of the affected fetus. Lamellar bodies suggestive of membranous cytoplasmic bodies were found in cells of basal ganglions, while the accumulation of GM1-ganglioside in the brain was not remarkable.