In 5% of cases, ALS is caused by a mutation in genes including TARDBP, SOD1 (cytosolic SOD), FUS, C9orf72, TAF15 and UBQLN2. Mutations in SOD1, increased oxidative and nitrosative stress and dramatic gliosis (aberrant astrocytes, extensive astrocytosis, upregulated inducible nitric oxide synthase (iNOS) expression and activated microglial cells) are some of the pathologic changes noted in ALS [77]. Here, UBQLN2 is linked to amyotrophic lateral sclerosis.