Deletion of a non-imprinted 500kb genomic region at chromosome 15q11.2, between breakpoints 1 and 2 of the Prader–Willi/Angelman locus (BP1–BP2 deletion), has been associated in previous studies with phenotypes including congenital cardiovascular malformations (CVM). This evidence concerns the gene IGFBP2 and congenital heart malformation.