SAT-420 Interaction Between Gene Polymorphisms and Urine Iodine Levels on Susceptibility to TPOAb Positivity in the Chinese Population

Objective: Hashimoto thyroiditis, characterized by positive thyroid peroxidase antibodies (TPOAbs), is caused by the interaction of genetic and environment factors. The aim of this study was to clarify the interaction of gene polymorphisms and iodine intake in the incidence of TPOAb positivity. Methods: 1733 subjects were included in this study. Genomic DNA was extracted from peripheral blood white cells. Seven SNPs (rs10944479, rs11675434, rs1230666, rs3094228, rs653178, rs9277555 and rs301799) were selected for genotyping. Thyroid hormones and autoimmune antibodies (TPOAb and TGAb) were determined using the electrochemiluminescence immunoassay method. Results: The mean TSH level in TPOAb-positive subjects was higher than in TPOAb-negative subjects (P<0.001). There were no significant differences in urine iodine and blood iodine between these two groups. Genotype GG of rs9277555 and genotype TT of rs11675434 were associated with an increased risk of TPOAb positivity. Logistic regression analysis showed rs9277555 was associated with TPOAb positivity in all models. Furthermore, rs9277555 was also associated with TPOAb levels in linear regression analysis. The cross-validation consistency and the testing accuracy indicated that there were no significant differences between SNPs and urine iodine interaction. Conclusion: rs9277555 was associated with an increased risk of TPOAb positivity in a Chinese Han population. Furthermore, there was no gene polymorphisms-iodine intake interactions in our cohort.