BDNF rs 6265 polymorphism and COMT rs 4680 polymorphism in deficit schizophrenia in Polish sample

Background: Deficit schizophrenia (DS) is distinguished from the group of schizophrenic psychoses based on the presence of primary negative symptoms. It differs from nondeficit (NDS) forms of schizophrenia in dimensions such as risk factors, family history, course of illness and neurobiological differences. The aim of the study was assessment of a potential association of the investigated polymorphisms of the brain-derived neurotrophic factor (BDNF) and catechol-O-methyltransferase (COMT) genes with the deficit syndrome in schizophrenia. Methods: A cohort of 200 patients with schizophrenia (81 DS and 119 NDS subjects) and a group of 100 control subjects matched for ethnicity, sex and age were recruited. Somatic and psychometric assessment were conducted as well as structured interview about the influence of adverse biological, family and social factors. Genetic analysis of the BDNF (Va166Met) rs6265 and the COMT (Va1158Met) rs4680 polymorphisms was performed. Results: We found significant differences between DS and NDS in rs4680 COMT genotype distribution: more homozygous Val/Val were found (31 vs. 17%) in the NDS compared to the DS subgroup. No associations were found between the investigated polymorphisms of the BDNF gene and the presence of schizophrenia either in DS and NDS subgroups. Conclusion: The analysis of the COMT rs4680 polymorphism in the present DS and NDS study shows that some genetic factors may be relevant in analyzing the reasons for the differentiation of schizophrenic subtypes.