DRD2 and schizophrenia: Güzey C. et al. (2007) showed the frequency of carriage of the A allele of the DRD2 gene (Taq1A) was statistically significantly higher compared to the control group (p = 0.04), which confirms that the carriage of the A allele is associated with the risk of developing AIP in patients with schizophrenia [52].