Objective: Bronchial asthma is a complex inflammatory disorder shaped by genetic susceptibility and environmental exposures. This immunogenetic case-control study aimed to investigate the association between HLA class II genes and bronchial asthma in a Central Asian population chronically exposed to Aral Sea-related airborne pollutants.

Materials and Methods: High-resolution genotyping of the HLA-DQA1, HLA-DQB1, and HLA-DRB1 loci was performed in patients with bronchial asthma and age- and sex-matched conditionally healthy controls.

Results: Asthma patients exhibited markedly elevated total IgE levels and widespread allergen-specific sensitization, supporting the predominance of an IgE-driven allergic endotype. Significant associations with increased asthma risk were identified for the HLA- DQB103:03 and HLA-DRB107 alleles, whereas HLA-DRB110 and HLA-DRB111 demonstrated potential protective effects. No independent association was observed for HLA-DQA1 alleles.

Conclusion: This study provides the first immunogenetic evidence of HLA class II involvement in bronchial asthma within an environmentally stressed Central Asian population characterized by chronic exposure to Aral Sea-related airborne pollutants. These findings underscore the importance of gene-environment interactions and support the integration of immunogenetic markers into future risk stratification and personalized prevention strategies in high-exposure regions.