Distribution of allele and genotype frequencies for the IL5 rs2069812 polymorphism in occupational asthma according to its phenotype

Molecular genotyping opens up fresh opportunities to search for a more targeted and personalized approach to treating occupational asthma (OA) and to developing an individual strategy for its prevention.

Objective. To determine genetic risk markers for OA under the influence of sensitizers, by assessing IL5 rs2069812 polymorphic variants.

Subjects and methods. The investigation enrolled 170 patients with different OA phenotypes. The patients were divided into groups according to the OA phenotype: 1) 42 patients with an allergic OA phenotype; 2) 36 patients with a non-allergic OA phenotype; 3) 58 patients with an OA + occupational chronic obstructive pulmonary disease (COPD) phenotype; 4) 34 patients with an OA + metabolic syndrome (MS) phenotype. A control group included 50 healthy individuals. IL5 rs2069812 polymorphisms were determined as part of the study of genetic predisposition to OA. Phenol chloroform extraction was used to isolate DNA from peripheral lymphocyte samples. Genotyping was done by real-time polymerase chain reaction with primers and probes designed using the PrimerQuest program (Integrated DNA Technologies, Inc., USA).

Results. The genetic markers for OA were found for the first time after exposure to sensitizers, IL5 rs2069812 polymorphic variants, which can recommend that this genetic marker should be identified during thorough periodic medical examinations in individuals with clinical, functional, and immunological changes upon occupational exposure to sensitizing and irritating substances.

Conclusion. The identified marker profiles of the genotypes of OA can optimize an approach to diagnosing, treating, and preventing this disease, and expanding the range of criteria for predicting its course. When a polymorphism in the IL5 gene is detected using a molecular genetic study, the patient needs to be registered for follow-up, repeated respiratory function tests once every six months, thorough periodic medical examinations in a specialized center of occupational pathology, by obligatorily attracting a pulmonologist, an allergist/immunologist, and an occupational pathologist, as well as extensive functional and immunological studies once every two years.