UBA52 and proximal spinal muscular atrophy: Ubiquitin has been implicated in playing a role in several neurodegenerative diseases such as frontotemporal lobar degeneration [31]–[32], schizophrenia [33], Parkinson’s [34], spinal muscular atrophy [35], motor neuron disease/amyotrophic lateral sclerosis [36]–[40], often associated with filamentous inclusion bodies found in these types of disorder [31],[38].