It has been reported that, in mild ALS cases, MT-MMP-1, -2, -9, and TIMP-1 expressions are increased in the serum relative to CSF, where MMP-2, MT-MMP-1, and TIMP-1 were unchanged, while the levels of MMP-9 have been declined [160]. This evidence concerns the gene MMP9 and amyotrophic lateral sclerosis.