Influence of monoamine oxidase A and serotonin receptor 2A polymorphisms in SSRI antidepressant activity

Int J Neuropsychopharmacol. 2002 Mar;5(1):27-35. doi: 10.1017/S1461145701002711.


The aim of the present study was to test a possible effect of the monoamine oxidase A (MAOA) and serotonin receptor 2A (5-HT-2A) gene variants on the antidepressant activity of fluvoxamine and paroxetine in a sample of major (n = 248) and bipolar (n = 195) depressives, with or without psychotic features. A total of 443 in-patients were treated with 300 mg fluvoxamine (n = 307) or 20-40 mg paroxetine (n = 136) for 6 wk. The severity of depressive symptoms was assessed weekly with the Hamilton Rating Scale for Depression (HAMD). Allele variants were determined in each subject using a PCR-based technique. We observed a marginal association between 5-HT-2A variants and antidepressant response while MAOA genotypes were not associated. Possible stratification factors, such as sex, diagnosis, presence of psychotic features, HAMD scores at baseline, pindolol augmentation and SSRIs plasma levels did not significantly influence the observed results. The investigated MAOA and 5-HT-2A gene variants, therefore, do not seem to play a major role in SSRI antidepressant activity.

Publication types

  • Clinical Trial

MeSH terms

  • Adrenergic beta-Antagonists / therapeutic use
  • Antidepressive Agents, Second-Generation / therapeutic use*
  • Antimanic Agents / therapeutic use
  • Depressive Disorder / drug therapy*
  • Depressive Disorder / genetics*
  • Depressive Disorder / psychology
  • Depressive Disorder, Major / drug therapy
  • Depressive Disorder, Major / psychology
  • Double-Blind Method
  • Drug Synergism
  • Female
  • Fluvoxamine / therapeutic use
  • Genotype
  • Humans
  • Lithium / therapeutic use
  • Male
  • Middle Aged
  • Monoamine Oxidase / genetics*
  • Paroxetine / therapeutic use
  • Pindolol / therapeutic use
  • Polymorphism, Genetic / genetics
  • Polymorphism, Genetic / physiology*
  • Psychiatric Status Rating Scales
  • Receptor, Serotonin, 5-HT2A / genetics
  • Receptor, Serotonin, 5-HT2A / physiology*
  • Selective Serotonin Reuptake Inhibitors / therapeutic use*
  • Sex Characteristics


  • Adrenergic beta-Antagonists
  • Antidepressive Agents, Second-Generation
  • Antimanic Agents
  • Receptor, Serotonin, 5-HT2A
  • Serotonin Uptake Inhibitors
  • Paroxetine
  • Lithium
  • Pindolol
  • Monoamine Oxidase
  • Fluvoxamine