TREM2 and amyotrophic lateral sclerosis: On the other hand, an analysis of the frequency of the TREM2 p.R47H variant using a large cohort comprising AD, FTD, mild cognitive impairment, PSP, CBS, and amyotrophic lateral sclerosis (ALS) cases and controls did not find any significant links between the variant and neurodegenerative diseases other than AD [45].