DAOA and early-onset autosomal dominant Alzheimer disease: This association between GABRB2 with psychosis severity in SCZ is corroborated by parallel observations on other SCZ-candidate genes including: effects of COMT[20] and DISC[43] on psychosis severity in SCZ; GABRB2[26] and COMT[44] on occurrence of psychosis in BPD; COMT, DAOA and HTR2A on occurrence of psychosis in Alzheimer’s disease [22], [23], [45]; and dopamine dysfunction on occurrence of psychosis in SCZ [46].