C9orf72 and amyotrophic lateral sclerosis: In ALS motor neurons under free-uptake conditions with 10 μM oligonucleotide, ASO-577061 was less active against V3 than C9orf72-630 or C9orf72-631 (retaining 0.66-fold V3 expression compared with 0.12-fold and 0.16-fold, respectively, Supplementary Fig. 3h), and it was not active enough under these conditions to evaluate selectivity.