Consumptive hypothyroidism develops when the rate of inactivation of thyroid hormones surpasses the rate of their production, and this may be attributed to the presence of a high level of 3 iodothyronine deiodinase in the hemangioma tissue which catalyzes the conversion of T4 to rT3 and of T3 to diiodothyronine, both of which are biologically inactive[3]. The gene discussed is DIO3; the disease is hypothyroidism.