Diagnosis of smith-lemli-opitz syndrome

To the Editor: Tint et al. (Jan. 13 issue)¹ reported a biochemical defect in cholesterol biosynthesis that gives rise to a well-recognized dysmorphic syndrome, the Smith-Lemli-Opitz syndrome. Plasma from affected children contains a high concentration of the cholesterol precursor 7-dehydrocholesterol and a low level of cholesterol. The risk of recurrence of this autosomal recessive condition in a subsequent child is 1 in 4, and to date, prenatal ultrasound scanning has been of limited use². We have used biochemical testing to perform a successful prenatal diagnosis. The first child of the couple requesting the prenatal diagnosis had the Smith-Lemli-Opitz syndrome,.