Progressive Symmetric Erythrokeratodermia (PSEK): Phenotype Analysis And Mutation Detection

The term erythrokeratoderma (EK) means a heterogeneous group of disorders characterized by the mixture of erythematous and hyperkeratotic lesions by dissimilar mode; two major clinical subtypes have been described as erymrokeratodermia variabilis and progressive symmetric erythrokeratodermia. Both of them are autosomal dominant diseases with incomplete penetrance and variable expression and their molecular mechanism are unknown. Ishida-Yamamoto have acomplished serial study on PSEK, but his results had received suspicion from other researchers. To explore the penotype features, inheritance mode and molecular mechanism of PSEK patients in China, we analyzed the clinical features of 6 Chinese PSEK pedigrees which have been published since 1980 and performed mutation detection in some candidate genes by direct sequencing.The results about penotype shows: (1)most patients occurs during the first year or childhood, and the illness state fully develops in adulthood; (2)the typical lesion is hyperkeratotic erythematous with small scales, and some patients have distinguishing penotypes; (3)the disease transfer continuously in pedigrees, patients have no difference in gender and disease affect about half member in brethren; (4)clinical penotypes of most patients fully express but penetrance is not 100%.The results of mutation detection show there are no mutations on Loricrin gene and candidate genes of EKV (GJB3 and GJB4) .We concluded: (1)the penotype spectrum and inheritance feature of Chinese PSEK are similar with other ethnic group; (2)PSEK in Chinese group also shows high penetrance and variable expressivity; (3)the genetic mechanism of PSEK may exist mutation heterogeneity, or there are other genes take part in its pathogenesis, and more investigation are needed in discovery of the molecular mechanism of PSEK.