Lack of Mutations in P450scc Gene (CYP11A) in Six Japanese Patients with Congenital Lipoid Adrenal Hyperplasia

Abstract

Congenital lipoid adrenal hyperplasia (CLAN) results from deficient cholesterol side chain cleavage activity in both adrenal and gonadal mitochondria. Previous studies, however, have failed to disclose a defect in the P450scc gene in six patients studied to date.To investigate further a cause-and-effect relationship between a mutation in the P450scc gene and congenital lipoid adrenal hyperplasia phenotype, we studied the P450scc genes from five Japanese families, in which at least one member had the entity (six patients and 10 unaffected members), by direct sequencing of all the nine exons and by linkage analysis using restriction fragment length polymorphism and microsatellite polymorphism.No major rearrangement or minor mutation was found in the entire exonic sequences of the gene in the six patients. The particular copy of the P450scc gene as defined by the microsatellite polymorphism did not cosegregate with the disease in one informative family.We conclude that the primary lesion in congenital lipoid adrenal hyperplasia does not reside in the P450scc gene in most, if not all, of the patients.