Prenatal diagnosis of Hunter syndrome using chorionic villi

A case of the Hunter syndrome diagnosed prenatally using chorionic villi is presented. Chorion biopsy was performed in the 10th week of pregnancy. The sample was examined for karyotype and for iduronate sulfatase activity. The fetus was male and the enzyme activity reduced to 4 per cent of normal. Termination of pregnancy occurred at the 11th week.