G6PC1 and type 2 diabetes mellitus: Importantly, excessive HGP causes hyperglycemia and glucose intolerance, hallmarks of type 1 and type 2 diabetes.[1] Glucose‐6‐phosphatase converts glucose 6‐phosphate to glucose, a key step of both glycogenolysis and gluconeogenesis.[1] Hepatocytes prominently express glucose‐6‐phosphatase catalytic subunit 1 (G6pc) which determines the rate of HGP.