C9orf72 and amyotrophic lateral sclerosis: For genetic variation as the ML label, we set the label = 1 for those ALS samples carrying more than 30 GGGGCC repeats in C9ORF72 or intermediate (i.e., 30–33,) CAG repeats in ATXN2, and label = 0 for those ALS samples who did not meet the previous criteria.