The TARDBP gene variant is a known major cause of amyotrophic lateral sclerosis (ALS), with limited reports of Korean patients with ALS harboring the variants in TARDBP. This large cohort study introduces four ALS patients who share the p.M337V variant of the TARDBP, allowing for an investigation of clinical characteristics and prognosis by analyzing previously reported cases with the same variant. The gene discussed is TARDBP; the disease is amyotrophic lateral sclerosis.