Apart from suggesting the involvement of activated mitogen-activated protein (MAP) kinases (extracellular signal-regulated kinase: ERK and p38) in the interrelation of T2DM and IVDD [58,60,63], signaling pathways shared by T2DM and IVDD pathogeneses were further addressed in detail in the 23 studies included. This evidence concerns the gene MAPK14 and type 2 diabetes mellitus.