USP9X and atypical Rett syndrome: Further examination of the “nervous system development” gene ontology set showed that it included not only critical genes for neurodevelopment, but also genes associated with high-risk for ASD (e.g. AFF2 and CHD8), genes implicated in neuronal syndromes (USP9X), and genes found to be translationally dysregulated in Rett syndrome cortical neurons (NEDD4L) (Fig. 4C; Supplementary Table 2).