Two novel mutations of the nicastrin gene in Chinese patients with acne inversa.

Acne inversa (AI, OMIM 142690), also called hidradenitis suppurativa, is a chronic, inflammatory, recurrent and debilitating skin follicular disease that usually presents after puberty with painful, deep-seated, inflamed lesions in the apocrine gland-bearing areas of the body, most commonly the axilla, inguinal and anogenital regions.(1) The prevalence of AI has been estimated at 1 in 100 to 1 in 600.(2) Of patients with AI, 35-40% have a positive family history.(3) The pattern of transmission is consistent with autosomal dominant inheritance.(4) In 2006, Gao et al.(5) mapped the AI gene at chromosome 1p21.1-1q25.3. In 2010, Wang et al.(6) were the first to identify mutations of gamma-secretase genes responsible for AI among six Chinese families. gamma-Secretase is a transmembrane protease composed of four essential protein subunits: one catalytic presenilin (PSEN1) subunit and three cofactor subunits [presenilin enhancer 2 (PSENEN), nicastrin (NCSTN) and anterior pharynx defective 1 (APH1)]. Two, one and three mutations were found in PSENEN, PSEN1 and NCSTN, respectively. Here, we report a heterozygous nonsense c.1695T>G mutation and a heterozygous missense c.632C>G mutation of the NCSTN gene in two Chinese AI families.