DHCR7 genotypes of cousins with Smith‐Lemli‐Opitz syndrome

Smith-Lemli-Opitz syndrome (SLOS) is an autosomal recessive disorder of cholesterol biosynthesis caused by mutations of the 7-dehydrocholesterol reductase gene (DHCR7). We report on three cousins with SLOS, all of whom were found to be compound heterozygotes for the common splice site mutation IVS8-1G-->C and the missense mutation T289I. DNA analysis of one set of parents demonstrated that the father carried the missense mutation and the mother …