Contribution of Antigen-Processing Machinery Genetic Polymorphisms to Atopic Dermatitis.

Atopic dermatitis (AD) is a chronic and recurrent inflammatory dermatosis. We recently described an association of the allele of the single nucleotide polymorphism (SNP) in the gene and a synergism of ERAP1 and ERAP2 effects on AD risk. Here, we examined whether polymorphisms of other antigen-presenting machinery genes encoding immunoproteasome components LMP2 and LMP7 and peptide transporter components TAP1 and TAP2 may also affect susceptibility to AD or its outcome. We found that the allele decreased disease risk by about 1.5-fold (odds ratio 0.66, 95% confidence interval 0.44-0.99). On the other hand, the allele reduced the mean age at diagnosis from 23 to 15 years ( < 0.001). Similarly, the allele decreased the mean age at diagnosis from almost 20 to 14 years ( = 0.033). The results are discussed in light of other reports on the role of these polymorphisms in human disease.