Novel mutations in two families with Darier's disease.
BACKGROUND: Darier's disease (DD) is an autosomal dominant skin disorder characterized by abnormal keratinization and acantholysis. Deleterious mutations in the gene ATP2A2 which encodes SERCA2, a calcium pump of the sarco/endoplasmic reticulum underlie the disease. OBJECTIVE: To identify the genetic defect in two Jewish families of eastern-European ancestry with DD. METHODS: DNA was extracted from peripheral blood of six patients and three healthy members of the two families. Polymerase chain reaction (PCR) was carried out to amplify the exons and flanking intron boundaries of the ATP2A2 gene followed by direct sequencing. Restriction fragment analysis verified the presence or absence of the mutations. Results Two novel mutations were identified. A nonsense mutation, a change of C391 to T (R131X) in exon 5, was found in one family and a missense mutation, a change of A530 to C (Q177P) in the second. The mutations were not present in 50 healthy individuals of the same ethnic origin. Both pathogenic mutations are in codons that are located in a highly conserved cytoplasmic beta-strand domain which functions as the transduction site. CONCLUSION: The existence of two mutations in two Jewish families of the same ancestry might confirm the previously published reports that most mutations in that gene are private.