We previously described two independently derived ENU-induced mouse Disc1 missense mutants which provides an opportunity to test this hypothesis, since they exhibit distinct behavioral abnormalities related to depression (Disc131L/31L) and schizophrenia (Disc1100P/100P), and affect binding of DISC1 to PDE4 and GSK3β [11], [12]. Here, DISC1 is linked to major depressive disorder.