DTNBP1 and substance-induced psychosis: DTNBP1 variants (including e.g., protective and risk haplotypes) are reported to affect susceptibility to substance-induced psychosis [12], and dysbindin-1 is involved in regulation of synaptic plasticity [6,9], neurotransmitter release [3-5], and membrane surface expression of NMDA and D2 receptors [6-8].