title: Frequency and ethnic distribution of the common DHCR7 mutation in Smith-Lemli-Opitz syndrome.
abstract: Smith-Lemli-Opitz syndrome (SLOS) is an inherited multiple malformation syndrome caused by enzymatic deficiency of 3beta-hydroxysterol-Delta(7)-reductase (DHCR7). SLOS is thought to be most common among European Caucasians, with an incidence of 1 in 20,000 to 1 in 30,000 births. To define the carrier rate and ethnic distribution of SLOS, we screened DNA samples from 2,978 unrelated individuals for the most common SLOS mutation (IVS8-1G-->C). Twenty-four heterozygotes of the IVS8-1G-->C mutation were detected in 2,978 individuals of European Caucasian and Black backgrounds. For European Caucasians, the carrier rate for SLOS may be as high as 1 in 30, suggesting an incidence of 1 in 1,700 to 1 in 13,400. This high number is supported by the recent observation of newborn and prenatal incidence of 1 in 22,000 in the Caucasian population. Ours is the first report of the IVS8-1G-->C mutation in persons of African ancestry. Published 2001 Wiley-Liss, Inc.
authors.affiliation: Department of Pathology and Molecular Medicine, McMaster University, 1200 Main Street West, Hamilton, Ontario L8S 4JP, Canada. nowaczyk@hhsc.ca
authors.forename: M J
authors.initials: MJ
authors.lastname: Nowaczyk
authors.forename: L M
authors.initials: LM
authors.lastname: Nakamura
authors.forename: B
authors.initials: B
authors.lastname: Eng
authors.forename: F D
authors.initials: FD
authors.lastname: Porter
authors.forename: J S
authors.initials: JS
authors.lastname: Waye
mesh_terms: D005060:Europe / Q000453:epidemiology / Q000208:ethnology; D005787:Gene Frequency / Q000235:genetics*; D006580:Genetic Carrier Screening; D005820:Genetic Testing; D006801:Humans; D009154:Mutation / Q000235:genetics*; D010088:Oxidoreductases / Q000235:genetics*; D044925:Oxidoreductases Acting on CH-CH Group Donors; D019082:Smith-Lemli-Opitz Syndrome / Q000201:enzymology* / Q000208:ethnology / Q000235:genetics*
chemical_list: D010088:Oxidoreductases; D044925:Oxidoreductases Acting on CH-CH Group Donors; C019995:7-dehydrocholesterol reductase