title: ABCB1 C3435T polymorphism is associated with susceptibility to major depression, but not with a clinical response to citalopram in a Turkish population.
abstract: BACKGROUND
  The ATP-binding cassette sub-family B member 1 (ABCB1) gene, which encodes the p-glycoprotein at the blood-brain barrier, is investigated for patients' susceptibility to major depressive disorder (MDD) and their therapeutic response to antidepressants. However, there is an inconsistency between the studies of different ethnic groups. The current study aimed to determine the potential correlations of the ABCB1 gene C3435T polymorphism with the susceptibility to MDD and the therapeutic response to citalopram in a Turkish population.
  
  
  METHODS
  Fifty-four patients with MDD who received citalopram and 70 controls from the Turkish population were genotyped for ABCB1 C3435T polymorphism. To assess the therapeutic response to citalopram, all patients were rated baseline, first, second, fourth and sixth weeks according to the 17-item Hamilton Rating Scale for Depression (HAMD-17).
  
  
  RESULTS
  There was a significant correlation between the patient and control groups for ABCB1 C3435T polymorphism. Distribution of CC genotype and C allele frequency were higher in the patients than in the control group (p = 0.006, p = 0.020, respectively). However, no correlation between ABCB1 C3435T polymorphism and a therapeutic response to citalopram was observed.
  
  
  CONCLUSIONS
  Our results suggested that C3435T polymorphism in the ABCB1 gene may be an indicator of the susceptibility to major depression, without a likely treatment response to citalopram in a Turkish population. These findings should be replicated in studies on larger patient groups with different ethnicities.
authors.affiliation: Akdeniz University, Medical Faculty, Department of Pharmacology, Antalya, Turkey. Electronic address: gulozbey@akdeniz.edu.tr.
authors.forename: Gul
authors.initials: G
authors.lastname: Ozbey
authors.affiliation: Ministry of Health of Turkey, General Directorate of Pharmaceuticals and Pharmacy, Clinical Drug Trials Department, Ankara, Turkey.
authors.forename: Berna
authors.initials: B
authors.lastname: Yucel
authors.affiliation: Gaziosmanpasa University Medical Faculty, Department of Psychiatry, Tokat, Turkey.
authors.forename: Serap E
authors.initials: SE
authors.lastname: Taycan
authors.affiliation: Gazi University Medical Faculty, Department of Genetics, Ankara, Turkey.
authors.forename: Derya
authors.initials: D
authors.lastname: Kan
authors.affiliation: Erenkoy Psychiatry and Neurology Education and Research Hospital, Department of Psychiatry, Istanbul, Turkey.
authors.forename: Nurdan E
authors.initials: NE
authors.lastname: Bodur
authors.affiliation: Bal?kesir State Hospital, Department of Psychiatry, Bal?kesir, Turkey.
authors.forename: Tayyibe
authors.initials: T
authors.lastname: Arslan
authors.affiliation: Gazi University Medical Faculty, Department of Genetics, Ankara, Turkey.
authors.forename: Ferda
authors.initials: F
authors.lastname: Percin
authors.affiliation: Gazi University Medical Faculty, Department of Genetics, Ankara, Turkey.
authors.forename: Nevzat
authors.initials: N
authors.lastname: Yuksel
authors.affiliation: Department of Research and Development, Division of Psychiatry, St Olavs University Hospital, Trondheim, Norway; Department of Neuroscience, Faculty of Medicine, Norwegian University of Science and Technology, Norway.
authors.forename: Cuneyt
authors.initials: C
authors.lastname: Guzey
authors.affiliation: Gazi University Medical Faculty, Department of Pharmacology, Ankara, Turkey.
authors.forename: Canan
authors.initials: C
authors.lastname: Uluoglu
mesh_terms: D018435:ATP Binding Cassette Transporter, Subfamily B / Q000235:genetics; D000328:Adult; D018687:Antidepressive Agents, Second-Generation / Q000627:therapeutic use*; D015283:Citalopram / Q000627:therapeutic use*; D003865:Major Depressive Disorder / Q000188:drug therapy* / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic
chemical_list: C513055:ABCB1 protein, human; D018435:ATP Binding Cassette Transporter, Subfamily B; D018687:Antidepressive Agents, Second-Generation; D015283:Citalopram
keywords: ABCB1; Citalopram; Depression; Polymorphism; Response