title: Investigation of epistasis between DAOA and 5HTR1A variants on clinical outcomes in patients with schizophrenia.
abstract: OBJECTIVE
  In two recent studies of our group, rs10042486, a single-nucleotide polymorphism (SNP) within 5HTR1A, and rs7139958, a SNP within the d-amino acid oxidase activator (DAOA) were found to be associated with clinical improvement, as detected by the positive symptom subscale of the Positive and Negative Symptoms Scale (PANSS) in a sample 221 Korean schizophrenia patients treated with various antipsychotics.
  
  
  METHODS
  The existence of possible epistatic interactions between rs10042486 and rs7139958 influencing PANSS-positive subscale improvement scores in the same sample was investigated.
  
  
  RESULTS
  No significant epistatic interaction was observed. Furthermore, the independent associations observed between rs10042486, rs7139958, and PANSS-positive subscale improvement scores in earlier studies were no longer significant when they were included in our model.
  
  
  CONCLUSIONS
  Although limited by some methodological shortcomings, our results preliminarily point to the possibility that positive genetic associations observed in some samples could not be replicated in different samples because of the existence of consistent differences in the genotype frequencies of other genetic polymorphisms that epistatically interact with the specific variants under investigation in a given study.
authors.affiliation: Institute of Psychiatry, University of Bologna, Bologna, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Chiesa
authors.forename: Loredana
authors.initials: L
authors.lastname: Lia
authors.forename: Changsu
authors.initials: C
authors.lastname: Han
authors.forename: Soo-Jung
authors.initials: SJ
authors.lastname: Lee
authors.forename: Chi-Un
authors.initials: CU
authors.lastname: Pae
authors.forename: Alessandro
authors.initials: A
authors.lastname: Serretti
mesh_terms: D000328:Adult; D044466:Asian People; D002352:Carrier Proteins / Q000235:genetics*; D004843:Epistasis, Genetic; D005260:Female; D014644:Genetic Variation; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D044282:Receptor, Serotonin, 5-HT1A / Q000235:genetics*; D012559:Schizophrenia / Q000235:genetics*
chemical_list: D002352:Carrier Proteins; C475071:DAOA protein, human; D047908:Intracellular Signaling Peptides and Proteins; D044282:Receptor, Serotonin, 5-HT1A