AITD is a complex genetic disease, and the genes leading to AITD disease can be divided into two categories: immunomodulatory genes, including human leukocyte antigen (HLA), cytotoxic T lymphocyte-associated antigen 4 (CTLA-4), protein tyrosine phosphatases, nonreceptor type 22 (PTPN22), CD40, CD25, and Fc receptor-like 3 (FCRL3) genes, as well as thyroid-specific genes, including thyroid-stimulating hormone receptor (TSHR) and thyroglobulin (Tg); however, currently, there is no evidence that any of these genes are associated with SLC12A3 [20]. The gene discussed is PTPN22; the disease is hereditary disease.