Clinical and genetic analysis of a pedigree with acne inversa

Abstract

Objective To detect γ-secretase gene mutations in a large Chinese pedigree with acne inversa (AI).Methods Clinical evaluation was carried out in a large pedigree with AI through field investigation.Peripheral blood samples were obtained from 17 family members (11 affected and 6 unaffected) and 100 unrelated healthy human controls.DNA was extracted from the blood samples,and PCR was performed to amplify all the coding regions of PSEN 1,PSENEN and NCSTN genes followed by DNA sequencing analysis.Results There were 67 members over 5 generations in this family,of whom,25 (13 males and 12 females) were affected by AI.AI was inherited in an autosomal dominant manner in this family.Skin lesions were mainly distributed on the neck,back,chest and buttocks,and occasionally in subaxillary regions.DNA sequencing revealed a novel missense mutation,c.1258C＞ T (p.Q420XP),in the exon 11 of the NCSTN gene in 11 affected family members,which leads to a substitution of glutamine by a premature termination codon at amino acid 420 (p.Q420X).The mutation was undetected in either the unaffected members or the unrelated healthy controls,and had not been registered in the single nucleotide polymorphism (SNP) database in National Center for Biotechnology Information.Conclusions There is a novel heterozygous missense mutation,c.1258C ＞ T in the exon 11 of the NCSTN gene,which may be the molecular basis of pathogenesis of AI in this family. Key words: Acne inversa; Phenotype; Mutations