MTHFD1 and type 2 diabetes mellitus: We further found 29 of the analyzed genes to exhibit differential expression in both skeletal muscle from twins with T2D and in myotubes from subjects with T2D when compared with the respective controls based on nominal P < 0.05 (Additional file 1: Supplemental Table 7 and Additional file 1: Supplemental Fig. 1B), including MTHFD1 and TXNIP, the latter was previously shown to be upregulated in skeletal muscle from subjects with prediabetes and T2D and it was inversely correlated with glucose uptake [29].