COMT and psychotic disorder: Recent research suggests that COMT (either genotype) or AKT1 (either genotype) alone is not sufficient to cause psychosis; therefore, these genes may have true etiological effects only when combined with frequent early exposure to THC or with younger age, increasing frequency, or high doses of exposure to THC, particularly for those with other vulnerabilities such as early trauma, social adversity, or pre-existing subclinical symptoms.