SLC2A4 and Insulin resistance: This feature makes GLUT4 a key player in normal glucose homeostasis but also an important factor in insulin resistance (Ren et al., 1995; Leturque et al., 1996; Tsao et al., 1996) and glucose intolerance, two hallmarks of ALS (Reyes et al., 1984; Pradat et al., 2010; Dupuis et al., 2011; Sacca et al., 2012).