BCAAs	branched-chain amino acids
BCAT	branched-chain aminotransferase
BCKDH	branched-chain ketoacid dehydrogenases
BCKDC	branched-chain ketoacid dehydrogenase complex
BCKAs	branched-chain α ketoacids
MSUD	maple syrup urine disease
BCKDK	branched-chain ketoacid dehydrogenase kinase
BCKDP	branched-chain ketoacid dehydrogenase phosphatase
NBS	newborn screening
LC–MS/MS	liquid chromatography–tandem mass spectrometry
DBS	dried blood spot
Rr	reference range
Leu	leucine
Ile	isoleucine
Alloile	alloisoleucine
Val	valine
Phe	phenylalanine
WES	whole-exome sequencing
NGS	next-generation sequencing technology
KIC	α-ketoisocaproate