Another example of mutations in three important spliceosomal maintenance proteins (TDP-43, FUS/TLS, and SMN) cause profound loss of the spliceosomal integrity and lead to amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA) (Tsuiji et al., 2013). This evidence concerns the gene TARDBP and proximal spinal muscular atrophy.