title: Serotonin-related polymorphisms in TPH1 and HTR5A genes are not associated with escitalopram treatment response in Korean patients with major depression.
abstract: OBJECTIVE
  The genetic variations in serotonin-related genes may be associated with antidepressant treatment response in major depressive disorder (MDD). The tryptophan hydroxylase-1 (TPH1) gene and serotonin 5A receptor (HTR5A) gene are known to be involved in serotonin biosynthesis and signal transduction, respectively. The purpose of this study was to investigate a possible interaction between the TPH1 gene and the HTR5A gene in the treatment outcome of escitalopram in MDD.
  
  
  METHODS
  In total, 245 patients diagnosed with MDD were recruited, and their symptoms were evaluated using the 17-item Hamilton Depression Rating scale (HAMD-17). The association between the TPH1 218A/C and HTR5A 12A/T polymorphisms and the clinical outcomes (remission, response and changes in HAMD-17 score) was investigated after 2, 4 and 8 weeks of escitalopram treatment using multiple logistic regression or multiple linear regression analysis.
  
  
  RESULTS
  No significant associations of TPH1 or HTR5A gene polymorphisms were observed with either response rate or remission rate at 2, 4 and 8 weeks after escitalopram treatment. In addition, the gene-gene interaction between TPH1 and HTR5A genes was not associated with the treatment outcome.
  
  
  CONCLUSIONS
  Our results suggest that TPH1 218A/C and HTR5A 12A/T polymorphisms cannot predict treatment response in major depression.
authors.affiliation: Department of Psychiatry, College of Medicine, Korea University, Seoul, Republic of Korea.
authors.forename: Yong-Gu
authors.initials: YG
authors.lastname: Kim
authors.forename: Hun-Soo
authors.initials: HS
authors.lastname: Chang
authors.forename: Eun-Soo
authors.initials: ES
authors.lastname: Won
authors.forename: Byung-Joo
authors.initials: BJ
authors.lastname: Ham
authors.forename: Min-Soo
authors.initials: MS
authors.lastname: Lee
mesh_terms: D000928:Antidepressive Agents / Q000627:therapeutic use*; D044466:Asian People / Q000235:genetics; D015283:Citalopram / Q000627:therapeutic use*; D003865:Major Depressive Disorder / Q000188:drug therapy* / Q000235:genetics*; D005260:Female; D006801:Humans; D007723:Korea; D016014:Linear Models; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010597:Pharmacogenetics; D011110:Polymorphism, Genetic; D011569:Psychiatric Status Rating Scales; D011600:Psychopharmacology; D011985:Receptors, Serotonin / Q000235:genetics*; D013997:Time Factors; D016896:Treatment Outcome; D014365:Tryptophan Hydroxylase / Q000235:genetics*
chemical_list: D000928:Antidepressive Agents; D011985:Receptors, Serotonin; C078730:serotonin 5 receptor; D015283:Citalopram; C497467:TPH1 protein, human; D014365:Tryptophan Hydroxylase