DDX3X and neurodevelopmental disorder: Most cases of DDX3X variants have been reported in females but very rarely in males, and three previous large cohort studies have described heterogeneous clinical manifestations of DDX3X neurodevelopmental disorder, including ID or DD, dystonia, movement disorders, microcephaly, behavioral issues, feeding difficulties in infancy, and seizure (Snijders Blok et al., 2015; Wang et al., 2018; Johnson-Kerner et al., 2020; Lennox et al., 2020).