Notably, the patient harbouring p.P34R presented syntelencephaly, a rare brain malformation characterized by an abnormal midline connection of the cerebral hemispheres, suggesting a role of RAC3 in the cleavage process of prosencephalon.19 Meanwhile, p.G12R and p.K116N affect residues conserved in most small GTPases within the G1 and G4 boxes, respectively. This evidence concerns the gene RAC3 and midline interhemispheric variant of holoprosencephaly.