To further increase the complexity of the ALS picture, SOD1G93A mice have shown defects in cell-to-cell adhesion between the endothelial cells of the blood–spinal cord barrier, and a recent study supports a central contribution of the SOD1-mutant-mediated endothelial damage to disease initiation that may accumulate prior to MN degeneration and neurovascular inflammatory response (Zhong et al., 2008). Here, SOD1 is linked to amyotrophic lateral sclerosis.