The STR in STMN2, previously linked to ALS or ALS survival, failed our genotyping accuracy assessment and was not associated with ALS in other studies.35,77,78 The higher number of ALS patients with 24 CA repeat units reported in Theunissen et al. was not replicated, potentially due to tissue-specific differences (blood versus spinal cord motor neurons).35 Genotyping difficulties in STMN2 indicate that accurately determining its repeat size remains challenging across multiple methods. The gene discussed is STMN2; the disease is amyotrophic lateral sclerosis.