SUCLA2 and Mitochondrial myopathy: Nonetheless, on the organismal level, SUCLA2‐deficient mice present with severe muscular phenotypes suggestive of mitochondrial myopathy, which is further evidenced by elevations of circulating FGF‐21, lower serum creatinine suggestive of reduced muscle mass, mitochondrial proliferation and Type 1 fibre predominance (Figures 2e–f, 7 and 8) [4, 28, 31, 33, 34].