碘过量时DNA甲基化在自身免疫性甲状腺炎发病中的作用

碘缺乏和碘过量均会对机体产生不良影响，碘过量危害包括地方性甲状腺肿、亚甲减、自身免疫性甲状腺疾病、甲状腺结节发生率增加等。自身免疫性甲状腺疾病属于复杂疾病，是环境与遗传共同作用的结果，碘作为环境影响因素之一，流行病学调查已经证明碘能够增加自身免疫性甲状腺炎（AIT）的发病率，也有研究表明碘在AIT发病机制方面有一定的作用。本课题拟在碘过量、碘适宜和缺碘后补碘地区，选择AIT患者和对照，进行病例对照研究，采用全基因组Bisulfite测序进行全基因组DNA甲基化研究，比较AIT患者与对照全基因组DNA甲基化的差异；在此基础上选择相关基因和信号通路，进行验证研究，初步选出与AIT发生有关的DNA甲基化差异基因和信号通路，分析碘过量时DNA甲基化差异基因和信号通路在自身免疫甲状腺炎发病中的作用。本研究将促进对AIT发病机制的认识，并且可能为AIT的诊断和治疗提供新的手段。

Iodine deficiency and iodine excess will result in adverse effect to the body. Iodine excess disorders includes such as an increased incidence of endemic goiter, subclinical hypothyroidism, autoimmune thyroid diseases, and thyroid nodule. Autoimmune thyroid disease is a complex disease caused by the combination of environment and heredity. Epidemiological investigations have shown that iodine, as one of the environmental factors, can increase the incidence of autoimmune thyroiditis (AIT). And some studies show that iodine plays a role in the pathogenesis of AIT. In this project, a case-control study will be conducted in iodine excess area, iodine adequate area and iodide supplementation area. The differences of genome-wide DNA methylation between AIT group and control group will be studied by Whole Genome Bisulfite Sequencing. Base on this result, related genes and signal path will be selected and their DNA methylation will be investigated by MethylTarget Multi-purpose regional methylation enrichment sequencing technology. As a result, the DNA methylation loci and signal path of AIT will be selected preliminary and their contribution for the prevalence of AIT will be estimated. This study will promote the understanding of AIT pathogenesis and may provide new means for the diagnosis and treatment of AIT.