Determination of High-Resolution HLA-DQB1 Suballeles and IL-17 Polymorphisms in Turkish Pediatric Patients

Celiac disease (CD) is an autoimmune enteropathy in the small intestine caused by gluten intolerance of the patients. The most important genetic disease-related factor is human leukocyte antigen (HLA)-DQ polymorphism. Association between interleukin (IL)-17A expression of CD4 ⁺ T cells and various autoimmune diseases has been reported. The aim of this study was to investigate the relationship between single nucleotide polymorphism (rs2275913) IL-17A and HLA-DQ polymorphisms in Turkish pediatric celiac patients. Study group included 125 pediatric celiac patients with CD and 100 healthy pediatric controls. Deoxyribonucleic acid was isolated from peripheral blood samples. IL-17A polymorphism (rs2275913) was analyzed by polymerase chain reaction-restriction fragment polymorphism method. IL-17A polymorphism and low-/high-resolution HLA-DQ results of patients were evaluated. GG and GA genotype frequencies of IL-17A (rs2275913) polymorphism were significantly higher ( p  < 0.05) in the CD patients than the control group. HLA-DQB1*02 and HLA-DQA1*05 alleles were detected in patients, while HLA-DQB1*03 and HLA-DQA1*01 alleles in the control group. Also, when we compared the patient and control groups in terms of HLA-DQ-DR haplotypes, HLA-DQB1*02-DQA1*05-DRB1*03 was found with the relative risk of 42.5 ( p  < 0.05). As a result of high-resolution HLA-DQB1 typing, DQB1*02:01 and DQB1*03:02 were at high frequency ( p  < 0.05; in 25 patient group). IL-17A (rs2275913) polymorphism genotype frequency was found to be significant in the patient group compared with the control group. The most common HLA-DQB1 suballele was observed as DQB1*02:01.