ARG1 and hyperinsulinemic hypoglycemia, familial, 4: Argininosuccinate synthetase deficiency (ASSD), argininosuccinate lyase deficiency (ASLD) and arginase 1 deficiency (ARG1D) are distal UCDs, while hyperornithinemia-hyperammonemia-homocitrullinuria syndrome (HHHS) and citrin deficiency (Citrin D) are found by deficiencies in two mitochondria transport proteins [3].