SOD1 and amyotrophic lateral sclerosis: Interestingly, one of these was a patient with bulbar-onset ALS heterozygous for the D90A SOD1 mutation [17] with typical pTDP-43-positive neuropathology, supporting the hypothesis that the pathomechanism may be different in (some) D90A-heterozygous patients compared to SOD1D90Ahom patients.