Serum ferritin and transferrin levels are the key in the diagnosis, and cutoffs vary by gender with ferritin levels of >300μg/L and transferrin saturation of >50% in men and >200μg/L and 40% in women considered highly suggestive of hemochromatosis and, in the absence of other causes, warranting genetic testing. This evidence concerns the gene TF and hemochromatosis type 1.