A custom Agilent 1M array was designed with dense coverage (average probe spacing of 200 bp) of all putative de novo CNV regions. Samples were coded and hybridizations were done in random order to avoid any plate effects. Two-color hybridizations were performed with two micrograms of sample and reference DNA (CHP-SKN-1) and hybridized to the array at the Oxford Gene Technology service laboratory (Cambridgeshire, UK).
