MT-RNR1 and type 2 diabetes mellitus: Since we have previously demonstrated that high levels of physical activity can counteract the negative effect of functional MOTS-c deficiency on T2D risk11 and since exercise increases muscle CK2 activity (Figures 1D and 1E), we examined the interaction between MOTS-c SNP and physical activity levels on muscle mass in humans (Figure 6G; Table S18).