Giant occipitoparietal encephaloceles are rare forms of neurodevelopmental defects whose etiologies remain uncertain. Their occurrence can lead to variable neurological outcomes depending on the extent of cerebral cortex involved and the ability to repair the defect. In addition, encephaloceles may be associated with various genetic syndromes and familial inheritance. Here, the authors describe a unique constellation of malformations associated with the case of a giant occipitoparietal meningoencephalocele with herniation of cortical tissue and continuity with the ventricular system. The patient had a cleft lip and palate, hemivertebrae of the thoracic spine, a patent ductus arteriosus, a ventricular septal defect, and coarctation of the aorta. To identify the genetic underpinnings of these malformations, fluorescence in situ hybridization and microarray analysis were performed and revealed an 80.65-kb gain within chromosome band 2p11.2. Duplications of this region involving RMND5A, whose product contains a C-terminal to lis homology (LisH) domain, have not previously been associated with a defined phenotype but may present insight into encephalocele formation. Surgical repair and follow-up for the neurological malformations are also discussed.