PDE4B and schizophrenia: Thus, in much the same way as DISC1 was discovered at a translocation breakpoint (Blackwood et al., 2001; Millar et al., 2000; St Clair et al., 1990), PDE4B was found to be directly disrupted by a t(1:16) translocation in a proband with schizophrenia, who also had an affected cousin (Millar et al., 2005).