CHD2 and Global developmental delay: Some studies have demonstrated that pathogenic variants of the CHD2 gene are associated with childhood-onset developmental and epileptic encephalopathy (DEE), which is a severe form of neurodevelopmental disorder with a wide range of phenotypic variability, including autism spectrum disorder (ASD), intellectual disability (ID), developmental delay, microcephalus, behavioral anomalies, facial dysmorphisms, and several types of epilepsy (Carvill and Mefford, 2015; Thomas et al., 2015; Verhoeven et al., 2016; Chen et al., 2020).