Background： Acne inversa （AI）, also called hidradenitis suppurativa, is a chronic, inflammatory, recurrent skin disease of the hair follicle. Familial AI shows autosomal-dominant inheritance caused by mutations in the γ-secretase genes. This study was aimed to identify the specific mutations in the y-secretase genes in two Chinese families with AI. Methods： In this study, two Chinese families with AI were investigated. All the affected individuals in the two families mainly manifested with inultiple comedones, pitted scars, and a few inflammatory nodules on their face, neck, trunk, axilla, buttocks, upper arms, and thighs. Reticulate pigmentation in the flexures areas resembled Dowling-Degos disease clinically and pathologically. In addition, one of the affected individuals developed anal canal squamous cell carcinoma. Molecular mutation analysis of γ-secretase genes including PSENEN, PSENI, and NCSTN was performed by polymerase chain reaction and direct DNA sequencing. Results： Two novel mutations of PSENEN gene were identified, including a heterozygous missense mutation c. 194T〉G （p.L65R） and a splice site mutation c. 167-2A〉G. Conclusions： The identification of the two mutations could expand the spectrum of mutations in the γ-secretase genes underlying AI and provide valuable information for further study of genotype-phenotype correlations.
Background Human piebaldism is a rare autosomal dominant condition characterized by congenital white forelock and depigmented patches of skin,typically on the forehead,anterior trunk and extremities.Mutations in the KIT gene have been proposed to be responsible for the underlying changes in this disorder.The aim of this study was to identify gene mutation in a Chinese family with piebaldism.Methods A Chinese family with piebaldism presenting with white forelock and large depigmented skin macules on the abdomen,arms and legs was collected.DNA was isolated from peripheral blood of the family members.The encoding exons with flanking intron regions of the KIT gene were analyzed by polymerase chain reactions （PCR） and direct DNA sequencing.Besides,DNA extracted from 100 ethnically matched population individuals was as controls.Results A heterozygous missense mutation c.2590T〉C was identified in the patients of the family.This mutation converted a serine residue to proline （p.Ser864Pro）.The mutation was not found in their unaffected family members or normal controis.Conclusion A novel missense mutation c.2590 T〉C was found and it might play a significant role in the piebaldism phenotype in the family.
WEN Guang-dong ZHOU Cheng YU Cong DU Juan XU Qian-xi LIU Zheng-yi ZHANG Jian-zhong
