The association of HLA-DRB1 allele group but not HLA-B or ERAP1-rs7063 gene polymorphisms with atopic dermatitis.

Atopic dermatitis (AD) is one of the most common dermatoses. According to current data 2.6 % of the world's population suffer from AD. Atopic dermatitis is a multifactorial disease. The immune genes polymorphism is also associated with an increased risk of AD. The human leukocyte antigen (HLA) system is a group of genes that plays a crucial role in the immune response. The endoplasmic reticulum aminopeptidases ERAP (1 and 2) are trimming longer peptides to an optimal length for binding to HLA-I molecules. HLA class I (HLA-B) and class II (HLA-DRB1) typing and ERAP1-rs7063 genotyping were performed for 152 patients suffering from AD and 187 control subjects. Frequencies of HLA-B allele group and majority of HLA-DRB1 allele group did not differ between patients and controls. The exception was HLA-DRB1*07 allele group (OR = 0.34; 95 % CI = 0.20;0.61, p = 0.0039) whose frequency was lower in patients than in controls. ERAP1 19-exon to 20-exon ratio, governed by rs7063, did not seem to affect the susceptibility to AD.