description | Protein which, if defective, causes congenital hypothyroidism, a condition due to thyroid hormones deficiency, presenting at birth Congenital hypothyroidism occurs when the thyroid gland fails to develop or function properly. In most cases, the thyroid gland is absent, abnormally located, or severely reduced in size. In the remaining cases, a normal-sized or enlarged thyroid gland is present, but production of thyroid hormones is decreased or absent. If untreated, congenital hypothyroidism can lead to intellectual disability and growth failure |