Background: BCKDHA (branched chain keto acid dehydrogenase E1, alpha polypeptide) is a component of the branched-chain alpha-keto acid (BCAA) dehydrogenase (BCKD) complex. The BCKD complex is an inner mitochondrial enzyme complex that catalyzes the second major step in the catabolism of the branched-chain amino acids leucine, isoleucine, and valine. The BCKD complex consists of three catalytic components: a heterotetrameric (alpha2-beta2) branched-chain alpha-keto acid decarboxylase (E1), a dihydrolipoyl transacylase (E2), and a dihydrolipoamide dehydrogenase (E3). Mutations in this gene result in maple syrup urine disease, type IA [taken from NCBI Entrez Gene (Gene ID: 593)].