In our study, we observed enrichment between ALS and T1D, and identified three shared risk genes C9orf72, ZNF184, and ATXN2. Repeat expansions in C9orf72 is a frequent cause of ALS, and C9orf72 carriers tend to have autoimmune diseases more frequently, suggesting autoimmune inflammation may be intrinsically linked to ALS pathophysiology [59]. Here, C9orf72 is linked to autoimmune disease.