PPM1K and type 2 diabetes mellitus: BCAAs are the first amino acid group extensively studied in relation to the development of type 2 diabetes and remain the most widely researched to date [7] Branched-chain keto acid dehydrogenase kinase (BCKDK) is a kinase that inhibits BCKDH activity and targets branched-chain keto acid dehydrogenase E1 subunit alpha (BCKDHA), a gene that has been identified as one of the most likely candidate genes for T2DM [149].