For Fam7 with the initial diagnosis of mitochondrial disease (Table S1), a de novo missense variant in BCKDHA (BCKDHA:NM_000709:exon8:c.C1031T:p.A344V, BCKDHA:NM_001164783:exon8:c.C1028T:p.A343V) was retained after the multistep filtration. Here, BCKDHA is linked to mitochondrial disease.