Prenatal exclusion of metachromatic leukodystrophy by estimation of arylsulphatase A activity in chorion and cultured amniotic fluid cells.

Chorion biopsy specimens were used for prenatal assay of arylsulphatase A activity in a pregnant woman whose two children had died from metachromatic leukodystrophy (MLD). As in two subsequent pregnancies chorion arylsulphatase A was in the control range, it was concluded that both fetuses were healthy. Absence of MLD in the fetus from the first pregnancy was confirmed after assay of arylsulphatase A activity in fetal organs.