CUX2 and Delayed speech and language development: Recently, variants in CUX2 were found to be associated with developmental and epileptic encephalopathy 67 (DEE67, OMIM: 618141), an autosomal dominant disorder that typically manifests in infancy and is characterized by refractory seizures, global developmental delay with impaired motor and intellectual development, movement disorders, speech delay, and stereotypic or autistic behavior.