RAN and fragile X-associated tremor/ataxia syndrome: Previous intensive research discovered that small molecules, which selectively bound GGGGCC or CGG repeat RNA, prevented sequestration of an RBP and inhibited RAN translation in vitro and in vivo models of C9ALS/FTD or FXTAS (Su et al., 2014; Simone et al., 2018; Green et al., 2019).