SMN2 and proximal spinal muscular atrophy: We previously showed that nusinersen is more potent than morpholino/PDA-modified ASO10-29—a 2-nt longer version—in correcting SMN2 splicing in the central nervous system (CNS) of an SMA mouse model after ICV bolus injection, likely due to enhanced accumulation and/or slower clearance of nusinersen in this compartment (34).