CHL1 and Intellectual disability: Microarray analysis on our patient demonstrated that two genes, CNTN6 (MIM 607220) and CHL1 (MIM 607416) (which has been previously implicated in neuronal development associated to dendrite migration and mental retardation), are located within the deleted region and might implicate an haploinsufficiency mechanism, as loss of these genes has been related to mild mental deficit or do not present symptoms at all [26,27].