NRGN and schizophrenia: Compared with C allele carriers, NRGN gene rs12807809 TT homozygotes in patients with schizophrenia have significantly lower hippocampus-seeded FC values in bilateral middle cingulate gyri and left anterior cingulate gyrus, suggesting that rs12807809 may be involved in the pathophysiological process of abnormal Papez circuit function (Zhang et al., 2019).