Novel 7-DHCR mutation in a child with Smith-Lemli-Opitz syndrome

Smith-Lemli-Opitz syndrome (SLOS) is an autosomal recessive disorder charac terized by minor facial anomalies, mental retardation, and multiple congeni tal abnormalities. Biochemically, the disorder is caused by deficient activ ity of 7-dehydrocholesterol reductase, which catalyzes the reduction of the Delta 7 double bond of 7-dehydrocholesterol to produce cholesterol. Recent ly, mutations in the gene encoding 7-dehydrocholesterol reductase (7DHCR) w ere found to cause SLOS. We report the first molecular characterization of an Italian SLOS patient. Interestingly, his paternal 7DHCR allele, of Arab origin, harbored a novel P329L mutation which in combination with a materna l splice-site (IVS8-1 G>C) mutation resulted in a relatively milder phenoty pe. (C) 2000 Wiley-Liss, Inc.