Relationship between HLA-DQA1, -DQB1 gene polymorphism and susceptibility to pollen allergy in Russians

Background: Most common symptoms of pollen allergy in southern regions of Russia are allergic rhinitis (AR) sometimes in combination with comorbid bronchial asthma (BA). This project aimed to investigate why similar exposure to pollen may result in different symptoms among patients.
Objective: The main research objective was to identify a connection between whether susceptibility / resistance to different phenotypes of pollen allergy was associated with HLA class II genes in Russian ethnicity patients.
Methods: HLA-DRB1 and DQB1 genotyping was performed by PCR-SSP technique in 61 patients with symptoms of seasonal AR (n=31) and comorbid BA (n=30), as well as 94 healthy control subjects. The frequencies of alleles in patients and control group were compared with two-sided Fisher's exact test (p‐values <0.05 were considered significant).
Results: DRB1*08 is associated with a high risk of pollen allergy in Russian ethnicity patients (χ2=6.53; p<0.025), while DRB1*13 (χ2=6.90; p<0.01) and DQB1*03 (χ2=21.51; p<0.001) might be protective factors against pollen allergy. DRB1*15 (χ2=5.87; p<0.0025) and DRB1*08 (χ2=7.60; p<0.01) alleles are more frequent in patients with seasonal AR phenotype. DQB1*05 (χ2=4.04; p<0.05) allele is positively related with seasonal BA phenotype.Conclusions: Identified connection between HLA- DRB1 and DQB1 alleles in Russian ethnicity patients with pollen allergy and susceptibility / resistance to pollen allergy, as well as main clinical phenotypes of pollen allergy (AR and BA), will allow a better forecasting of BA debuts.