Mutation Analysis of the MVD Gene in a Chinese Family with Disseminated Superficial Actinic Porokeratosis and a Chinese Literature Review

BACKGROUND: Porokeratosis (PK) is a rare, heterogeneous group of keratinization disorders with an autosomal dominant inheritance pattern and is characterized by the presence of cornoid lamella. Disseminated superficial actinic PK is the most encountered subtype and typically manifests as multiple, small annular plaques with atrophic centers and slightly raised hyperkeratotic edges. Seven associated mutations (SSH1, SART3, MVKP, MVK, MVD, FDPS, and SLC17A9) have been reported in disseminated superficial actinic PK patients. AIM: We searched a Chinese disseminated superficial porokeratosis (DSAP) family to detect the causative genes. In the meantime, we reviewed the articles reported about DSAP in Chinese population, summarizing their clinical manifestations and discussing the incidence of DSAP in Chinese population. MATERIALS AND METHODS: Sanger sequencing on the MVD and MVK genes was performed to identify the pathogenic mutation in a Chinese family with DSAP. Literature for DSAP cases reported in Chinese populations was searched by Sinomed and PubMed. RESULTS: We identified the c. 875A > G (p. Asn292Ser) mutation in the MVD gene in the family. CONCLUSIONS: That mutation was a hotspot mutation. Literature review showed that the age of onset in DSAP family was earlier than that in sporadic patients; the lesion is common in the face in Chinese population which is distinct from studies in Caucasians; ultraviolet exposure is the main aggravating factor.