Liver diseases including chronic hepatitis C, cirrhosis, hepatocellular carcinoma (HCC), and cholangiocarcinoma affect thyroid function by changing thyroid hormone levels through altered production of binding proteins, modified deiodinase activity, and decreased liver clearance of reverse T3; these changes impact metabolic and energy balance, highlighting the importance of careful thyroid function monitoring in liver disease patients [95]. The gene discussed is TG; the disease is hepatocellular carcinoma.