The moderating effect of the Va166Met polymorphism of brain-derived neurotrophic factor gene on the clinical and psychological features of patients with schizophrenia
Golimbet, V.E.; Alfimova, M.V.; Korovaĭtseva, G.I.; Lezheĭko, T.V.
Molekuliarnaia Biologiia 48(1): 81-88
2014
ISSN/ISBN: 0026-8984 PMID: 25842828 Document Number: 677042
The brain-derived neurotrophic factor (BDNF) gene is a prominent candidate gene for schizophrenia. The BDNFVal66Met polymorphism has been extensively studied for association to this disease. There is accumulating evidence that the polymorphism is associated with clinical presentations of schizophrenia and not with the disease itself. We compared the allele and genotype distribution in patients (n=1785) and healthy controls (n = 1092) and did not find association of the Va166Met polymorphism with schizophrenia. No association was found with affective syndromes. At the same time, the ValVal genotype was associated with the higher anxiety level assessed with the PANSS in male patients. We studied personality characteristics using personality questionnaires EPI, MMPI, STAI (n=363) and cognitive functions (attention (n=227) and verbal fluency (n=392). Patients with the ValVal genotype demonstrated higher levels of anxiety assessed by the MMPI and better performance on the neurocognitive tests. The interaction effect of genotype and trait anxiety, measured with the STAI, on cognitive functions was identified. In patients with higher anxiety, the performance on cognitive tests did not depend on the genotype, while in patients with lower levels of anxiety the ValVal gen- otype was associated with the better performance. This effect should be taken into account when studying the association of the Val66Met polymorphism with cognitive functions in patients with schizophrenia.