We confirmed the association between C9orf72 and ATXN2 and ALS susceptibility, with the best thresholds aligning with those previously reported.27,44,57,69,70 Progression analysis validated C9orf72 as a modifier of ALS survival and age at onset, again with thresholds consistent with earlier findings.71-73 We found no compelling evidence that other STR loci are associated with ALS, even when considering repeat lengths shorter or longer than established pathogenic thresholds. Here, ATXN2 is linked to amyotrophic lateral sclerosis.