As for other metabolic disorders associated with aberrant mitochondrial bioenergetics, pathogenic AIFM1 mutations cause a large spectrum of clinical outcomes, including fatal encephalomyopathy, ataxia, late-onset neuromyopathy, and mild deafness8. This evidence concerns the gene AIFM1 and mitochondrial DNA depletion syndrome, encephalomyopathic form with methylmalonic aciduria.