SOD1 and amyotrophic lateral sclerosis: Apoproteins with a variety of ALS mutations (A4V, C146R, E100G, G85R, H46R, and I113T) formed amyloid at pH 7 in the presence of 1 M guanidine; no consistent effect of the mutations was observed, with some mutations forming more amyloid and others less amyloid than WT SOD1.