ABSTRACT
BACKGROUND: The role of single-nucleotide polymorphisms (SNPs) of the TNF gene in acne vulgaris remains controversial. METHODS: Genomic DNA was isolated from 185 patients with acne vulgaris and 165 healthy controls. SNPs at positions -376, -308 and -238 of the promoter region of TNF were defined. RESULTS: The frequency of the GAG haplotype was greater among patients (16.8%) than among controls with borderline significance (9.7%, p = 0.059). Male carriers of haplotypes other than GGG presented acne vulgaris at a later age than carriers of the GGG haplotype. No effect of the GAG haplotype on the frequency of acne conglobata was found among women with polycystic ovary syndrome. CONCLUSIONS: Carriage of the GAG haplotype of TNF is linked with borderline susceptibility to acne vulgaris. The GGG haplotype is related with earlier disease onset in male patients.
Subject(s)
Acne Vulgaris/genetics , Haplotypes/genetics , Tumor Necrosis Factor-alpha/genetics , Adolescent , Adult , Biomarkers/metabolism , Case-Control Studies , Genetic Predisposition to Disease , Genomics , Humans , Male , Polymorphism, Single NucleotideABSTRACT
Antigen presentation in chronic skin disorders is mediated through the interleukin (IL)-12/IL-23 pathway and, hence, through the IL-12 receptor. Recent evidence suggesting dysregulated antigen presentation in skin lesions of hidradenitis suppurativa (HS) led to investigate the role of single nucleotide polymorphisms (SNPs) of the gene IL-12RB1 coding for the IL12-Rß1 receptor subunit. Genomic DNA was isolated from 139 patients and 113 healthy controls; nine SNPs in the transcribed region of IL12RB1 were genotyped. No significant differences of genotype and allele frequencies were found between the two groups. Two common haplotypes were recognized, namely h1 and h2. Carriage of h2 related with minor frequency alleles was associated with a greater risk for the acquisition of Hurley III disease stage and with the involvement of a greater number of skin areas. Patients with the h1 haplotype presented disease at an older age. This is the genetic study enrolling the largest number of patients with HS to date. Although SNPs of IL12RB1 do not seem to convey genetic predisposition, they are associated directly with the phenotype of the disease.