Copy number variation studies of known disorders have the potential to improve the characterization of clinical phenotypes and may help identifying candidate genes and their pathways. The authors described a child with congenital heart disease, microcephaly, facial dysmorphisms, developmental delay, learning difficulties, and behavioral problems. There was initially a clinical suspicion of 22q11.2 deletion syndrome (22q11.2 DS), but molecular cytogenetic analysis (array genomic hybridization [aGH]) showed the presence of a de novo 3.6-Mb interstitial microdeletion in 8p23.1. The main features of 8p23.1 DS include congenital heart disease and behavioral problems, in addition to minor dysmorphisms and mental delay. Therefore, this article highlights the application of aGH to investigate 8p23.1 deletion in nonconfirmed 22q11.2 DS patients presenting neurobehavioral disorders, congenital cardiopathy, and minor dysmorphisms.