DRD3 and schizophrenia: Findings indicate that a number of genes is contributed to the development of schizophrenia, such as the brain-derived neurotrophic factor (BDNF), neurotrophic tyrosine kinase type 2 receptor (NTRK2), dopamine receptor D3 (DRD3), small conductance Ca2+-activated K+ channel protein 3 (SK3), and glycogen synthase kinase 3β (GSK3β) (18, 19).