SPAG5 and proximal spinal muscular atrophy: Overall, our data illustrate miR-34a-5p as a major player in cardiac pathologies of the SMA mouse model with Birc5, Spag5, circRNA007386, and potentially lncRNA00138536 as important downstream targets, although we do not rule out the possibilities that miR-34a or other factors may contribute to cardiac abnormalities in SMA mice via distinct pathways.