Circulatory stimulating TRAB is similar to TSH agonist and specifically binds to TSHR to stimulate the proliferation and hypertrophy of thyroid cell, promoting the expression of sodium-iodine cotransporter, thyroglobulin and thyroid peroxidase genes, and ultimately promote the production of thyroid hormone and hyperthyroidism (Smith and Hegedüs, 2016). Here, TG is linked to hyperthyroidism.