Similarly in vertebrates, altered expression or subcellular distribution of HDAC4 is associated with both neurodevelopmental and neurodegenerative disorders, including 2q37 syndrome (previously called brachydactyly mental retardation syndrome) (Williams et al., 2010; Morris et al., 2012; Villavicencio-Lorini et al., 2013), CDKL5 disorder (Trazzi et al., 2016), Alzheimer’s disease (Cao et al., 2008; Herrup et al., 2013; Shen et al., 2016), autism (Williams et al., 2010; Pinto et al., 2014). This evidence concerns the gene HDAC4 and early-onset autosomal dominant Alzheimer disease.