Lacking standard protocols for differentiation of hiPSCs to glial precursors; allowing the long-term survival; reducing the immune responses; mitigating the risk of tumor formation as well as establishing appropriate circuitry with host CNS. Several factors may account for the cell transplantation effects for ALS, including patient selection (disease stages), injection sites (cervical or lumbar or both), and modification of cellular grafts (glial-restricted precursors with/without GLT1 overexpression). This evidence concerns the gene SLC1A2 and amyotrophic lateral sclerosis.