Evidence for the absence of mutations at GJB3, GJB4 and LOR in progressive symmetrical erythrokeratodermia

P>Background. Progressive symmetrical erythrokeratodermia (PSEK) is a rare inherited cornification disorder characterized by symmetrical erythematous hyperkeratotic plaques. The genetic basis for PSEK is not clear. PSEK shares many clinical features with erythrokeratodermia variabilis (EKV), which is associated with mutations in genes coding for gap junction beta (GJB) 3 and 4. A mutation in the loricrin gene (LOR) was found in patients with PSEK, who were members of a family with Vohwinkel syndrome. It would therefore be of interest to determine if PSEK is also caused by mutations in these genes. Aim. To examine the mutation status of GJB3, GJB4 and LOR in patients with PSEK and in control subjects. Methods. Genomic DNA samples from 25 patients with PSEK and 56 healthy controls were examined by sequencing analysis of the coding sequences of GJB3, GJB4 and LOR. Results. There were no mutations found in any of these three genes. Conclusions. PSEK is a disorder distinct from EKV, and the true pathogenesis of PSEK remains unknown.