TP53 and proximal spinal muscular atrophy: There is mounting evidence that the activation of the tumor suppressor p53 pathway contributes to neuronal death in PD, AD, HD, and motor neuron diseases such as amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA) (Zhang et al., 2002; Chang et al., 2012; Qi et al., 2016; Simon et al., 2017; Vogt et al., 2018; Buettner et al., 2021; Maor-Nof et al., 2021).