Indeed, although the expression levels of miR-124 that regulate the expression levels of EAAT2 mRNA were significantly increased in the CSF of ALS patients [152], glutamate uptake in platelets were decreased not only in ALS patients, but also in AD and PD patients [188,205,206], and the EAAT2 levels in platelets from ALS patients were not statistically significantly different compared with those from control patients [207]. This evidence concerns the gene SLC1A2 and Parkinson disease.