FDX2 and Mitochondrial myopathy: Decreased activities also of complexes I, II, and III were described in cells with decreased Fdx2 content due to a mutation disrupting the ATG translation-initiation site, which is linked to mitochondrial myopathy (Spiegel et al., 2014), and defects in respiratory chain complex activities are known to be associated with other human disorders (Meunier et al., 2013).