Novel Mutations in PSENEN Gene in Two Chinese Acne Inversa Families Manifested as Familial Multiple Comedones and Dowling-Degos Disease.

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 γ-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 multiple 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, PSEN1, 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.