GPC1 and schizophrenia: Another schizophrenia GWAS study conducted by Potkin et al. in 2009 with 64 schizophrenia and 74 control subjects identified six genes (ROBO1-ROBO2, TNIK, CTXN3-SLC12A2, POU3F2, TRAF, and GPC1) significantly involved (p-value < 10−6) in forebrain development and the stress response pathway in schizophrenia [78].