Association of the brain-derived neurotrophic factor Val66Met polymorphism with negative symptoms severity, but not cognitive function, in first-episode schizophrenia spectrum disorders.
A functional polymorphism of the brain-derived neurotrophic factor gene (BDNF) Val66Met has been associated with cognitive function and symptom severity in patients with schizophrenia. It has been suggested that the Val66Met polymorphism has a role as a modulator in a range of clinical features of the illness, including symptoms severity, therapeutic responsiveness, age of onset, brain morphology and cognitive function. However, little work has been done in first-episode schizophrenia (FES) spectrum disorders. The objective of this study is to investigate the association of the BDNF Val66Met polymorphism on cognitive function and clinical symptomatology in FES patients.



Using a cross-sectional design in a cohort of 204 patients with FES or a schizophrenia spectrum disorder and 204 healthy matched controls, we performed BDNF Val66Met genotyping and tested its relationship with cognitive testing (attention, working memory, learning/verbal memory and reasoning/problem-solving) and assessment of clinical symptom severity.



There was no significant influence of the BDNF allele frequency on cognitive factor scores in either patients or controls. An augmented severity of negative symptoms was found in FES patients that carried the Met allele.



The results of this study suggest that in patients with a first-episode of schizophrenia or a schizophrenia spectrum disorder, the BDNF Val66Met polymorphism does not exert an influence on cognitive functioning, but is associated with negative symptoms severity. BDNF may serve as suitable marker of negative symptomatology severity in FES patients within the schizophrenia spectrum.
Barcelona clinic schizophrenia unit (BCSU), Institut clínic de neurociències (ICN), hospital clinic de Barcelona, Barcelona, Spain.
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Mezquida
Barcelona clinic schizophrenia unit (BCSU), Institut clínic de neurociències (ICN), hospital clinic de Barcelona, Barcelona, Spain; Department of psychiatry and clinical psychobiology, university of Barcelona, Barcelona, Spain; Institut d'investigacions biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Biomedical research networking centre in mental health (CIBERSAM), Barcelona, Spain.
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Penadés
Barcelona clinic schizophrenia unit (BCSU), Institut clínic de neurociències (ICN), hospital clinic de Barcelona, Barcelona, Spain; Biomedical research networking centre in mental health (CIBERSAM), Barcelona, Spain.
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Cabrera
Department of psychiatry, university of Cambridge, Cambridge, UK.
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Savulich
Biomedical research networking centre in mental health (CIBERSAM), Barcelona, Spain; Instituto de Investigación Sanitaria de Aragón (IIS Aragón), university of Zaragoza, Zaragoza, Spain.
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Lobo
Biomedical research networking centre in mental health (CIBERSAM), Barcelona, Spain; Araba university hospital, Bioaraba research institute, Araba, Spain; University of the Basque Country (UPV-EHU), Leioa, Spain.
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González-Pinto
Biomedical research networking centre in mental health (CIBERSAM), Barcelona, Spain; Child and adolescent psychiatry department, hospital general universitario Gregorio Marañón, school of medicine, universidad Complutense, Madrid, Spain.
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Penzol
Biomedical research networking centre in mental health (CIBERSAM), Barcelona, Spain; Department of psychiatry, institut d'investigació Biomèdica-Sant Pau (IIB-SANT PAU), hospital de la Santa Creu i Sant Pau, Barcelona, Spain; Universitat Autònoma de Barcelona (UAB), Barcelona, Spain.
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Corripio
Biomedical research networking centre in mental health (CIBERSAM), Barcelona, Spain; Behavioural and clinical neuroscience institute, university of Cambridge, Cambridge, UK.
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Fernandez-Egea
Institut d'investigacions biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Department of pathological anatomy, pharmacology and microbiology, university of Barcelona, Barcelona, Spain.
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Gassó
Department of psychiatry, Complejo Hospitalario de Navarra, Navarra, Spain; IdiSNA, Navarra institute for health research, Navarra, Spain.
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Cuesta
Barcelona clinic schizophrenia unit (BCSU), Institut clínic de neurociències (ICN), hospital clinic de Barcelona, Barcelona, Spain; Department of psychiatry and clinical psychobiology, university of Barcelona, Barcelona, Spain; Institut d'investigacions biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Biomedical research networking centre in mental health (CIBERSAM), Barcelona, Spain. Electronic address: bernardo@clinic.ub.es.
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Bernardo
D000328:Adult; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics*; D016022:Case-Control Studies; D003071:Cognition; D003430:Cross-Sectional Studies; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D008297:Male; D011110:Polymorphism, Genetic; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D012559:Schizophrenia / Q000235:genetics* / Q000503:physiopathology; D055815:Young Adult
D019208:Brain-Derived Neurotrophic Factor; C579455:BDNF protein, human
Clinical symptomatology; Genetics; Genotype; Neurocognition; Schizophrenia and psychosis