CYFIP2 and Intellectual disability: Specifically, in the case of CYFIP2, de novo variants have recently been identified in individuals diagnosed with neurodevelopmental disorders and early-onset epileptic encephalopathy characterized by developmental regression, intellectual disability, seizures, muscular hypotonia, and microcephaly (Nakashima et al. 2018; Peng et al. 2018; Lee et al. 2019; Zhong et al. 2019; Zweier et al. 2019; Begemann et al. 2021; Kang et al. 2023).