While the majority of patients harbor mutations in BCKDHA and BCKDHB genes, there is no characterized mouse model of MSUD linked to the Bckdhb gene, and only one report of a Bckdha knockout mouse with a severe phenotype and lethality within 24 h after birth and elevated BCAA and BCKA in plasma and tissues23. The gene discussed is BCKDHA; the disease is maple syrup urine disease.