• There was no difference in genotype and allele distributions of
BDNF Val66Met polymorphism between the patient and the
control groups which was interpreted as not being a genetic
predictor to show a predisposition to schizophrenia.
• The Met allele’s presence (Val/Met and Met/Met), which
means lower activity in the BDNF system, was found to be
associated with the risk of suicide attempts in patients with
schizophrenia.
• Poor performance in the the Stroop test was determined in
those having the Met allele compared to Val allele in patients
with schizophrenia.
• Having a Met allele may deepen the impairment in frontal
region functions such as focused attention and response
inhibition in patients with schizophrenia.
• BDNF gene Val66Met polymorphism has not been found to
play a role in areas such as executive functions, perseveration,
working memory, conceptualization, and abstract thinking as
measured by Wisconsin Card Sorting Test (WCST).
Introduction: The relationship between BDNF gene Val/Met
polymorphism and clinical symptoms, attention and executive functions
in patients with schizophrenia was investigated in this study. Also, BDNF
Val66Met gene polymorphism was compared between patients and
healthy controls. Thus, genetic factors that may affect both the etiology
and cognitive function of schizophrenia were evaluated.
Methods: BDNF Val66Met gene polymorphism was investigated in 102
patients with schizophrenia and 98 healthy controls. Cognitive functions
were evaluated by the Wisconsin Card Sorting Test (WCST) and Stroop
Test.
Results: There was no difference in terms of the genotypic or allelic
distribution of BDNF Val66Met polymorphism between patients and
healthy controls. A significantly higher percentage of suicide attempts
were found in the patients having Met allele (Val/Met and Met/Met).
Met allele was associated with failure in focused attention and response
inhibition in patients with schizophrenia.
Conclusion: The presence of the Met allele could be associated with
the risk of suicide attempts in patients with schizophrenia. Impairment
in executive function areas, such as focused attention and response
inhibition appears to be related to the Met allele.
Keywords: Schizophrenia, cognitive functions, BDNF, Val66Met
polymorphism