VGF and amyotrophic lateral sclerosis: While the exact functions of the peptides are in most cases still undetermined, it has been noted that in cerebrospinal fluid from ALS patients, immunoreactivity of the full-length VGF was reduced in parallel with development of ALS symptoms, leading the authors to hypothesize that restoring VGF expression in spinal cord motor neurons could therapeutically benefit clinical ALS [114].