Although some studies have shown baseline TPO and Tg antibody positivity to be more prominent in those who initially present with hypothyroidism and others have shown that these individuals require higher doses of levothyroxine, it is possible that the presence of TPO antibodies may simply reflect a humoral response to exposed thyroid antigens during a destructive process (8, 13) rather than autoimmunity. This evidence concerns the gene TG and hypothyroidism.