As noted in the case presentation, medical workup ruled out many possible etiologies of her hypertransaminasemia including cirrhosis, autoimmune and viral hepatitis, cholestasis, alpha-1 antitrypsin deficiency, Wilson’s disease, pre-eclampsia, HELLP syndrome, and acute fatty liver of pregnancy. The gene discussed is SERPINA1; the disease is hyperinsulinemic hypoglycemia, familial, 4.