NRXN1 and schizophrenia: Finally, a small study using genome-wide SNP discovery on 54 patients with deficit schizophrenia found and validated four rare schizophrenia-associated CNVs [44], two deletion affecting NRXN1 (see above), and ASTN2, and two duplications affecting 4 and 7 genes respectively, at 2p16.3 and 5p15.2.