High levels of DNA polymerase β mRNA corresponding with the high activity in Graves’ thyroid tissue

Introduction High DNA polymerase β activity has been observed in the thyroid tissue of patients with Graves’ disease (Nagasaka et al. in Metabolism 37:1051–1054, 1988). This fact aroused our interest in whether the alteration of DNA polymerase β activity depends on DNA polymerase β (DNA poly β) mRNA levels, which may be modulated by thyroid-stimulating hormone (TSH) or thyroid-stimulating substances, i.e. TSH receptor antibody (TRAb).