Consistent with this notion, our previous studies in αMNs from an SMA patient and the SMNΔ7 mouse have shown that the αMN degeneration caused by SMN deficiency includes an early depletion of canonical CBs and relocalization of coilin as perinucleolar caps and/or within the nucleolus18,25. Here, COIL is linked to proximal spinal muscular atrophy.