Mutations in the mevalonate pathway genes in Chinese patients with porokeratosis.

BACKGROUND: Porokeratosis (PK, MIM 175800) is a chronic autosomal dominant cutaneous keratinization disorder, which has a wide variety of clinical manifestations. OBJECTIVES: We analysed the molecular basis of 10 families and 12 sporadic cases with different subtypes of porokeratosis in the Chinese population. METHODS: Genomic DNA was extracted from peripheral blood samples. Mutation screening was performed by direct sequencing of exons and flanking intron-exon boundaries for the entire coding region of four mevalonate pathway genes and SLC17A9 gene. RESULTS: We detected three novel mutations and seven previously described mutations by direct sequence analysis of the PCR products. Mutations p.Phe249Ser and p.Asn292Ser in mevalonate decarboxylase (MVD) were the most common mutations in this PK cohort; their presence was 27.3% and 13.6% respectively. CONCLUSIONS: This study extended the mutation spectrum of PK in the Chinese Han population and provided further evidence for the genetic basis of PK. We first identified MVD simultaneously responsible for porokeratosis palmaris et plantaris disseminate development and confirmed the genotype-phenotype correlations.