Additional baseline screen for other causes of chronic liver disease can be considered, including investigations for hemochromatosis (iron binding capacity with genetic testing if iron saturation exceeds 0.60), autoimmune hepatitis (including primary biliary cholangitis where appropriate, ANA, anti-smooth muscle antibody, anti-mitochondrial antibody, and immunoglobulin levels), Wilson's Disease (ceruloplasmin), and alpha-1-antitrypsin deficiency. The gene discussed is BTG3; the disease is hyperinsulinemic hypoglycemia, familial, 4.