MAP2K1 and obesity due to melanocortin 4 receptor deficiency: Corroborating with this, myotubes from subjects with obesity showed several proteins regulating the cellular stress response to be upregulated, including mitogen-activated protein (MAP) kinase 1, sulfiredoxin-1 and glutathione peroxidase one indicating increased cellular oxidative stress in myotubes from this donor group (Supplementary Table S1).