Interestingly, in SMA cases involving SMN1 mutations, alterations congregate within either the TUDOR domain or the tyrosine- and glycine-rich (YG-rich) oligomerization domain (reviewed in Lomonte et al [2020]), suggesting that SMN oligomerization and TUDOR-mediated protein–protein interactions are biologically implicated in the SMA pathology. This evidence concerns the gene SMN2 and proximal spinal muscular atrophy.