Genetic determinants of aggression in schizophrenia: The role of MAOA rs1465108 and BDNF rs6265 polymorphisms

Studies have reported that the prevalence of aggression is higher in individuals with schizophrenia compared to the general population. Various factors, including genetic variations, contribute to the emergence of aggression in patients with schizophrenia. Among these, the monoamine oxidase A (MAOA) and brain-derived neurotrophic factor (BDNF) genes are considered key genetic factors potentially influencing aggressive behavior in schizophrenia. This study investigated the association of BDNF rs6265 and MAOA rs1465108 polymorphisms with aggression in schizophrenia. A total of 150 patients diagnosed with schizophrenia were included in the study. The MAOA rs1465108 and BDNF rs6265 polymorphisms were analyzed using the Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) method. Aggression was evaluated using the Buss-Perry Aggression Questionnaire. Suicide risk, childhood trauma, and impulsivity which were related to aggression were evaluated using the Suicide Probability Scale, the Childhood Trauma Questionnaire, and the Barratt Impulsiveness Scale, respectively. Negative and positive symptoms of schizophrenia were assessed using the Scale for the Assessment of Negative Symptoms (SANS) and the Scale for the Assessment of Positive Symptoms (SAPS), respectively. No direct genotype associations were observed between aggression and the BDNF rs6265 and MAOA rs1465108 polymorphisms. However, impulsivity, SAPS, and SANS scores were significantly associated with aggression. These findings highlight that aggression in schizophrenia is primarily shaped by environmental and clinical factors rather than by BDNF or MAOA variants.