Fig. 1

A) Pedigree of the family. B) Brain MRI with sagittal T1-weighted sequence (a) and axial (b-c-e-f) and coronal (d) T2-weighted sequences, performed respectively at 6 months of age (b-c) and 2 years old (a-d-e-f). A thin posterior corpus callosum is evident (a), involving the body, the isthmus and the splenium, with consequent dysmorphic temporal horns (d). A delayed myelination is evident at 6 months (b-c) as lack of diminution of signal intensity within the centrum semiovale, bilaterally (c) and in the corpus callosum (b); in the control MRI, myelination is complete (e-f), with evidence of numerous perivascular spaces within the white matter (f). Frontal cortical thickening is evident, with irregularity of the cortical-white matter junction (c-f) in both hemispheres, consistent with PMG . C) Sequencing chromatograms of DNA samples from the proband and the parents. The position of the novel DDX3X variant identified is indicated by a red box. The proband is confirmed to be heterozygous for the DDX3X c.625C > G variant, while parents are wild-type