IGFBP2 and attention deficit-hyperactivity disorder: The BP1-BP2 region contains genes critical for brain development and function, including non-imprinted in Prader-Willi/Angelman syndrome 1 (NIPA1), non-imprinted in Prader-Willi/Angelman syndrome 2 (NIPA2), cytoplasmic FMR1 interacting protein 1 (CYFIP1), and tubulin gamma complex associated protein 5 (TUBGCP5), which have been linked to conditions such as attention-deficit/hyperactivity disorder (ADHD), obsessive-compulsive disorder (OCD), and epilepsy.