Moreover, it has been demonstrated that dysregulated MECP2 activity and resulting epimutations in maternally imprinted UBE3A gene are linked to Angelman syndrome (AS), a NDD associated with hippocampal, cerebellar and cortical malfunctions, causing cognitive and language impairments, microcephaly, ataxia and epileptic seizures (Supplementary Table S1; Williams et al., 2010; Mastrototaro and Sessa, 2018; Maranga et al., 2020). This evidence concerns the gene MECP2 and Neurodevelopmental delay.