OTC and hyperinsulinemic hypoglycemia, familial, 4: Due to the liver's essential role in metabolism and systemic delivery of proteins into blood, many inherited and acquired diseases, such as hemophilia (A and B), α − 1 antitrypsin deficiency, and ornithine transcarbamylase deficiency, affect the liver and can potentially be corrected by liver-targeted gene therapy [2, 3, 72, 118].