We previously conducted a Drosophila screen of candidate proteins that bound with moderate-to-high affinity to G4C2 RNA and identified modulation of the nucleocytoplasmic transport (NCT) pathway as a potent modifier of G4C2 toxicity in both fly and iPS neuron models of C9-ALS (Zhang et al., 2015a), a finding that has also been made by other groups (Freibaum et al., 2015; Jovičić et al., 2015). The gene discussed is C9; the disease is amyotrophic lateral sclerosis.