A study evaluating HT patients showed that 47% of HT patients were ANA positive, and 72% of them have other autoimmunity parameters besides anti-thyroid peroxidase (anti-TPO) or antithyroglobulin (anti-Tg), and/or have an autoimmune disease besides HT [28], indicating that it is possible for HT patients to come out with other autoimmune diseases. This evidence concerns the gene TPO and autoimmune disease.