title: Evidence for a combined genetic effect of the 5-HT(1A) receptor and serotonin transporter genes in the clinical outcome of major depressive patients treated with citalopram.
abstract: In the context of a long-term follow-up study, we analysed the possible implication of the 5-HT(1A) receptor gene (HTR1A) -1018C/G polymorphism in the clinical outcome of major depressive patients treated with citalopram. We had previously reported an association between variation on the SERT gene (SLC6A4) and clinical remission after citalopram treatment. In the present 12-week follow-up study, the combined effect of HTR1A and SLC6A4 genes in clinical outcome and response to citalopram was also evaluated. The sample consisted of 130 patients, all of Spanish origin, who were diagnosed as having a current major depressive episode according to DSM-IV criteria. A 21-item Hamilton Depression Rating Scale was used to assess severity of symptoms at the beginning and during the follow-up to determine the outcome and remission status at week 12. Patients were genotyped for HTR1A gene and, in addition, for two polymorphisms at the CYP2C19 gene, which together account for the 87% of the Caucasian poor metabolizer phenotype. Data were analysed adjusting for the effect of poor metabolizers in clinical response. No independent effect was found for the 5-HT(1A) receptor gene in relation to clinical outcome or remission after citalopram treatment. However, a combined genetic effect of HTR1A and SLC6A4 genes was found to influence the clinical outcome of patients [F(4,102) = 2.89, p= 0.02]. When considering the remission status, an increase of patients carrying the risk genotype combination (S/S-G/G) was found among those subjects who did not reach remission (Fisher's exact test = 0.009). Our results suggest that the combined effect of the serotonin transporter and the 5-HT(1A) receptor genes could be related to the clinical outcome of depressive patients treated with citalopram.
authors.affiliation: Unitat d'Antropologia, Departament de Biologia Animal, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain.
authors.forename: Bárbara
authors.initials: B
authors.lastname: Arias
authors.forename: Rosa
authors.initials: R
authors.lastname: Catalán
authors.forename: Cristóbal
authors.initials: C
authors.lastname: Gastó
authors.forename: Blanca
authors.initials: B
authors.lastname: Gutiérrez
authors.forename: Lourdes
authors.initials: L
authors.lastname: Fañanás
mesh_terms: D000328:Adult; D000483:Alleles; D015283:Citalopram / Q000627:therapeutic use*; D004247:DNA / Q000235:genetics; D003865:Major Depressive Disorder / Q000188:drug therapy* / Q000235:genetics* / Q000523:psychology; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics*; D026901:Membrane Transport Proteins / Q000235:genetics*; D009419:Nerve Tissue Proteins / Q000235:genetics*; D011110:Polymorphism, Genetic; D011569:Psychiatric Status Rating Scales; D044282:Receptor, Serotonin, 5-HT1A / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D050486:Serotonin Plasma Membrane Transport Proteins; D017367:Selective Serotonin Reuptake Inhibitors / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D015283:Citalopram; D004247:DNA; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D044282:Receptor, Serotonin, 5-HT1A; D050486:Serotonin Plasma Membrane Transport Proteins; D017367:Selective Serotonin Reuptake Inhibitors; C493230:SLC6A4 protein, human