ACAD9 and inborn mitochondrial myopathy: The analysis of a panel of 368 nuclear genes involved in mitochondrial cytopathies highlighted two variants in the ACAD9 gene: a c.1240C> T p.Arg414Cys class 5 variant, which is already described, and a c.1636G> A p.Val546Met class 3 or 4 variant, which has never been identified or reported (Figure 1A).