title: Reduced hippocampus volume and memory performance in bipolar disorder patients carrying the BDNF val66met met allele.
abstract: Previous studies investigated the impact of brain-derived neurotrophic factor (BDNF) val66met (rs6265) on hippocampus volumes and neurocognition in bipolar disorders (BD), but the results were not consistent. This study aimed to investigate the effect of BDNF polymorphism on hippocampus volumes and memory performance in well-characterized adult populations diagnosed with type I BD (BD-I) and major depressive disorder (MDD) compared with healthy controls (HC).
  
  
  
  48 BD-I patients, 33 MDD patients and 60 HC were genotyped for BDNF rs6265 using DNA isolated from white blood cells. Individuals with val/met and met/met genotypes were grouped as met carriers and compared to those with the val/val. Brain segmentations were obtained from structural magnetic resonance imaging (MRI) using the Freesurfer. Memory performance was assessed with the California Verbal Learning Task (CVLT).
  
  
  
  We found a significant diagnosis effect and marginal interaction between diagnosis and BDNF genotype group for both hippocampus volumes and memory performance. BDNF met allele carrier BD patients had smaller hippocampus volumes and reduced performance on multiple CVLT scores compared to MDD patients and HC.
  
  
  
  We provide strong evidence for the BDNF val66met polymorphism as a putative biological signature for the neuroanatomical and cognitive abnormalities commonly observed in BD patients.
authors.affiliation: Department of Psychiatry and Behavioral Sciences, The University of Texas Health Science Center at Houston, Houston, TX, United States. Electronic address: CloudBoCao@gmail.com.
authors.forename: Bo
authors.initials: B
authors.lastname: Cao
authors.affiliation: Department of Psychiatry and Behavioral Sciences, The University of Texas Health Science Center at Houston, Houston, TX, United States.
authors.forename: Isabelle E
authors.initials: IE
authors.lastname: Bauer
authors.affiliation: Department of Psychiatry and Behavioral Sciences, The University of Texas Health Science Center at Houston, Houston, TX, United States.
authors.forename: Ajaykumar N
authors.initials: AN
authors.lastname: Sharma
authors.affiliation: Department of Psychiatry and Behavioral Sciences, The University of Texas Health Science Center at Houston, Houston, TX, United States.
authors.forename: Benson
authors.initials: B
authors.lastname: Mwangi
authors.affiliation: The Center for Pediatric Behavioral Health and Center for Autism, Cleveland Clinic, Cleveland, OH, United States.
authors.forename: Thomas
authors.initials: T
authors.lastname: Frazier
authors.affiliation: Department of Psychiatry and Behavioral Sciences, The University of Texas Health Science Center at Houston, Houston, TX, United States.
authors.forename: Luca
authors.initials: L
authors.lastname: Lavagnino
authors.affiliation: Department of Psychiatry and Behavioral Sciences, The University of Texas Health Science Center at Houston, Houston, TX, United States.
authors.forename: Giovana B
authors.initials: GB
authors.lastname: Zunta-Soares
authors.affiliation: Department of Psychiatry and Behavioral Sciences, The University of Texas Health Science Center at Houston, Houston, TX, United States.
authors.forename: Consuelo
authors.initials: C
authors.lastname: Walss-Bass
authors.affiliation: The Olin Neuropsychiatry Research Center, Institute of Living, and Department of Psychiatry, Yale University School of Medicine, CT, United States.
authors.forename: David C
authors.initials: DC
authors.lastname: Glahn
authors.affiliation: Department of Psychiatry, Universidade Federal Rio Grande do Sul, Rua Ramiro Barcelos, 2350, 90035-903 Rio Grande do Sul, Brazil.
authors.forename: Flavio
authors.initials: F
authors.lastname: Kapczinski
authors.affiliation: Department of Psychiatry and Behavioral Sciences, Michael E. DeBakey V.A. Medical Center, Baylor College of Medicine, Houston, TX, United States.
authors.forename: David A
authors.initials: DA
authors.lastname: Nielsen
authors.affiliation: Department of Psychiatry and Behavioral Sciences, The University of Texas Health Science Center at Houston, Houston, TX, United States.
authors.forename: Jair C
authors.initials: JC
authors.lastname: Soares
mesh_terms: D000328:Adult; D000483:Alleles; D001714:Bipolar Disorder / Q000150:complications* / Q000235:genetics / Q000523:psychology; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics*; D003865:Major Depressive Disorder / Q000150:complications* / Q000235:genetics / Q000523:psychology; D005260:Female; D005838:Genotype; D006624:Hippocampus / Q000000981:diagnostic imaging / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008569:Memory Disorders / Q000150:complications* / Q000235:genetics / Q000523:psychology; D009929:Organ Size; D020641:Polymorphism, Single Nucleotide / Q000235:genetics
chemical_list: D019208:Brain-Derived Neurotrophic Factor; C579455:BDNF protein, human
keywords: BDNF val66met; Bipolar; Bipolar disorder type I; Hippocampus; MRI; Major depressive disorder; Memory; Polymorphism; Volume