Evaluation of IL17A (rs4711998) and IL18 (rs1946518) gene polymorphisms in individuals with anti-TPO-positive serum levels and healthy individuals with normal Anti-TPO: a case-control study

Abstract

Autoimmune thyroid disease (AITD) is one of the most common organ-specific autoimmune disorders. Inflammatory cytokines such as IL-17A and IL-18 are increasingly recognized as an important mediator in AITD. The present study was conducted with the aim of investigating IL-18 (Rs1946518) and IL-17A (Rs4711998) gene polymorphisms in Anti-TPO positive and negative patients. Methods: In this clinical trial study, 82 Anti-TPO positive patients (mean age 41.48 ± 9.58 years) were introduced by the laboratory. Then serum levels of vitamin D, TSH, and anti-TPO were measured. Based on TSH levels, they were divided into two categories: case and control. After blood sampling and DNA extraction, IL-18 (Rs1946518) and IL-17A (Rs4711998) gene polymorphisms were investigated using the tetra-ARMs PCR technique. Results: The results of our study showed that the difference in the frequency of Rs1946518 genotypes including TT and TG between the case and control groups was not significant (P>0.05). Regarding Rs4711998 genotypes, there was no significant frequency difference for GG between case and control groups (P=0.009). AA and AG genotype showed a significant difference between the two groups. The obtained OR is also significant and the AA and AG genotype increases the probability of the disease. Examination of the Hardy-Weinberg equilibrium of Rs1946518 and Rs4711998 for the case individuals showed that the difference observed for the observed and expected genotypes between the two groups was significant and the population was out of equilibrium.