title: Genetic variants of the BDNF and DRD3 genes in bipolar disorder comorbid with anxiety disorder.
abstract: BACKGROUND
  The high comorbidity rate between bipolar disorder (BP) and anxiety disorder (AD) has been studied in depth. This comorbidity is not as high in Han Chinese in Taiwan. Therefore, we explored the genetic effects BP comorbid with AD.
  
  
  METHODS
  We recruited 1316 participants: 286 with BP-I, 681 with BP-II, and 349 healthy Controls. Genotypes of the BDNF Val66Met and DRD3 Ser9Gly polymorphisms were determined using polymerase chain reactions plus restriction fragment length polymorphism analysis.
  
  
  RESULTS
  The DRD3 Ser9Gly polymorphism was associated with BP-II comorbid with AD (BPII(+AD)), and the BDNF Val66Met polymorphism was associated with BP-I comorbid with AD (BPI(+AD)). An interaction between the Val/Val genotype of the BDNF Val66Met and Gly/Gly polymorphism of the DRD3 Ser9Gly was found in BPII(+AD), but not in BP-II not comorbid with AD (BPI(-AD)) compared with healthy Controls.
  
  
  CONCLUSIONS
  The low comorbidity rate of AD in both BP subtypes, especially BP-I, limit generalizing our findings.
  
  
  CONCLUSIONS
  The involvement of the dopaminergic pathway in AD was confirmed, particularly with BP-II rather than BP-I. Because the Val/Val genotype of the BDNF Val66Met polymorphism, rather than the other two polymorphisms, has been associated with anxiety, it seems to affect BP-I comorbid with AD without the involvement of the DRD3 Seg9Gly polymorphism, but may modify the involvement of DRD3 Gly/Gly in BP-II comorbid with AD.
authors.affiliation: Division of Clinical Psychology, Institute of Allied Health Sciences, Tainan, Taiwan; Department of Psychiatry, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Yun-Hsuan
authors.initials: YH
authors.lastname: Chang
authors.forename: Sheng-Yu
authors.initials: SY
authors.lastname: Lee
authors.forename: Shiou-Lan
authors.initials: SL
authors.lastname: Chen
authors.forename: Nian-Sheng
authors.initials: NS
authors.lastname: Tzeng
authors.forename: Tzu-Yun
authors.initials: TY
authors.lastname: Wang
authors.forename: I Hui
authors.initials: IH
authors.lastname: Lee
authors.forename: Po See
authors.initials: PS
authors.lastname: Chen
authors.forename: San-Yuan
authors.initials: SY
authors.lastname: Huang
authors.forename: Yen Kuang
authors.initials: YK
authors.lastname: Yang
authors.forename: Hui-Chen
authors.initials: HC
authors.lastname: Ko
authors.forename: Ru-Band
authors.initials: RB
authors.lastname: Lu
mesh_terms: D000328:Adult; D001008:Anxiety Disorders / Q000453:epidemiology / Q000235:genetics*; D044466:Asian People / Q000235:genetics; D001714:Bipolar Disorder / Q000453:epidemiology / Q000235:genetics*; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics*; D016022:Case-Control Studies; D015897:Comorbidity; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008297:Male; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D050637:Receptors, Dopamine D3 / Q000235:genetics*; D013624:Taiwan / Q000453:epidemiology
chemical_list: D019208:Brain-Derived Neurotrophic Factor; C493593:DRD3 protein, human; D050637:Receptors, Dopamine D3
keywords: Anxiety comorbidity; BDNF; Bipolar subtypes; DRD3; Gene–gene interaction