UNC80 and Global developmental delay: A diagnosis of UNC80-related disorder should be considered in individuals presenting with global developmental delay (often with severe motor impairment), absent speech, neonatal hypotonia, profound intellectual disability, strabismus, limb dyskinesia, postnatal growth failure, postnatal microcephaly in some cases, sleep disturbances, irritability, constipation, and early-onset seizures [4,5,7].