In addition, patients with CDKL5 mutations are more often characterized by global developmental delay, cortical visual impairment and severely impaired gross motor function, while patients with FOXG1 mutations are more frequently reported to have postnatal microcephaly, typically associated with corpus callosum abnormalities and marked dyskinetic movements [200,201,202,203]. This evidence concerns the gene CDKL5 and microcephaly.