β ‐Glucuronidase deficiency: Enzyme studies in an affected family and prenatal diagnosis

Abstract

Aβ-glucuronidase deficiency found in serum, leukocytes and fibroblasts and an increased [³⁵S]sulphate incorporation in fibroblasts led us to diagnose two cases of type VII mucopolysaccharidosis in one family. In spite of the wide distribution of activities in serum from controls, decreasedβ-glucuronidase activity allowed us to demonstrate the heterozygous status of the parents and two other children. Following these studies, an antenatal diagnosis was performed when the mother was pregnant again; amniotic fluid and cultured amniotic cells were used for enzyme activity determination. A heterozygous fetus was suspected and confirmed after birth. The reliability of various biological materials for enzymatic diagnosis and existence of genetic variants in the normal population are discussed.