title: Transmission distortion of BDNF variants to bipolar disorder type I patients from a South American population isolate.
abstract: Recent reports have implicated polymorphisms in the brain derived neurotrophic factor (BDNF) gene region in the etiology of several psychiatric phenotypes, including bipolar disorder. Significant disease association has been reported for the G allele at SNP rs6265, which encodes for Valine at position 66 of BDNF (Val66Met), an apparently functional variant of this key BDNF. Here we examined a sample of 224 bipolar type I patients and available parents (comprising a total of 212 nuclear families) ascertained in a South American population isolate (Antioquia, Colombia). We tested for transmission distortion to bipolar patients of alleles at the rs6265 polymorphism and at a microsatellite marker 1.3 kb away from this SNP. Significant excess transmission of the rs6265 G allele to cases was observed (chi(2) = 10.77, d.f. = 1, P = 0.001). Two-locus haplotype analysis showed a significant global transmission distortion (chi(2) = 16.059, d.f. = 7, P = 0.025) with an excess transmission of a haplotype comprising the rs6265 G allele and microsatellite allele 227. These results are consistent with previous studies pointing to a role for BDNF in susceptibility to mood disorders.
authors.affiliation: Galton Laboratory, Department of Biology, University College London, London, United Kingdom.
authors.forename: Barbara
authors.initials: B
authors.lastname: Kremeyer
authors.forename: Ibi
authors.initials: I
authors.lastname: Herzberg
authors.forename: Jenny
authors.initials: J
authors.lastname: Garcia
authors.forename: Emily
authors.initials: E
authors.lastname: Kerr
authors.forename: Constanza
authors.initials: C
authors.lastname: Duque
authors.forename: Vicky
authors.initials: V
authors.lastname: Parra
authors.forename: Jorge
authors.initials: J
authors.lastname: Vega
authors.forename: Carlos
authors.initials: C
authors.lastname: Lopez
authors.forename: Carlos
authors.initials: C
authors.lastname: Palacio
authors.forename: Gabriel
authors.initials: G
authors.lastname: Bedoya
authors.forename: Jorge
authors.initials: J
authors.lastname: Ospina
authors.forename: Andres
authors.initials: A
authors.lastname: Ruiz-Linares
mesh_terms: D000483:Alleles; D001714:Bipolar Disorder / Q000235:genetics*; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics*; D003105:Colombia; D018900:Dinucleotide Repeats / Q000235:genetics; D005192:Family Health; D005260:Female; D005787:Gene Frequency; D006239:Haplotypes; D006801:Humans; D015810:Linkage Disequilibrium; D008297:Male; D020125:Mutation, Missense; D009679:Nuclear Family; D020641:Polymorphism, Single Nucleotide
chemical_list: D019208:Brain-Derived Neurotrophic Factor