The HLA-DRB1 Polymorphism is Associated With Atopic Dermatitis, but not Egg Allergy in Korean Children

PURPOSE We investigated whether particular HLA-DRB1 polymorphisms contribute to egg allergy development in Korean children with atopic dermatitis (AD). METHODS HLA-DRB1 alleles were determined by PCR-sequence-specific oligonucleotide (SSO) and PCR-single-strand conformation polymorphism (SSCP) methods in 185 patients with AD and 109 normal control (NC) subjects. AD patients were divided into two groups: 1) AD with egg allergy, consisting of 96 patients with egg allergies as determined by egg-specific immunoglobulin E (IgE) reactivity; and 2) AD without egg allergy, consisting of 89 patients without egg allergies. HLA-DRB1 alleles were classified into functional groups (A, De, Dr, E, Q, R, a). HLA-DRB1 phenotype and functional group frequencies in the AD, AD with egg allergy, and AD without egg allergy groups were compared with those in the NC group. RESULTS The frequency of DRB1(*)08:02 was decreased in the AD with egg allergy group compared with the AD without egg allergy group (2.1% vs. 10.1%, P=0.021), and DRB1(*)15:01 was increased in the AD with egg allergy group compared with the AD without egg allergy group (22.9% vs. 11.2%, P=0.036). However, significance was lost after Bonferroni correction. HLA-DRB1(*)11:01 had a significantly higher frequency in AD patients compared with NCs (12.4% vs. 1.8%, corrected P=0.048) and was regarded as a susceptibility factor associated with AD. DRB1(*)08:03 was decreased in AD patients compared with NCs (10.8% vs. 19.3%, P=0.043). HLA-DRB1 functional group 'a', which includes DRB1(*)15:01, seemed to be associated with the development of egg allergy in AD (P=0.033), but this result was not significant after Bonferroni correction. CONCLUSIONS HLA-DRB1 polymorphism is not associated with egg allergy, but HLA-DRB1(*)11:01 is associated with AD in Korean children.