Similarly, glucagon is known to stimulate hepatic amino acid catabolism for gluconeogenesis36; in all models of glucagon deficiency, the phenotype of the mutant mice mirrors that of Lkb1KOlivad, with the operation of a similar amino acid catabolism program and increases in the levels of most amino acids in the plasma, and many amino acids in the liver37–39. Here, GCG is linked to hyperinsulinemic hypoglycemia, familial, 4.