Given that NDN regulates migration of interneurons, and UBE3A is involved in the maturation of late-born neurons, it is therefore plausible that lack of these two genes would result in brain-wide deficits of the cortical mantle formation due to effects on intra-cortical connectivity, however having limited effect on cortical thickness in children with PWS. Here, NDN is linked to Prader-Willi syndrome.