title: 5-Hydroxytryptamine (serotonin) 2A receptor gene polymorphism is associated with schizophrenia.
abstract: OBJECTIVE
  Schizophrenia, the debilitating neuropsychiatric disorder, is known to be heritable, involving complex genetic mechanisms. Several chromosomal regions associated with schizophrenia have been identified during the past; putative gene (s) in question, to be called the global signature for the pathophysiology of the disease, however, seems to evade us. The results obtained from the several population-wise association-non association studies have been diverse. w0 e therefore, undertook the present study on Tamil speaking population in south India to examine the association between the single nucleotide polymorphisms (SNPs) at the serotonin receptor gene (5HT2A) and the occurrence of the disease.
  
  
  METHODS
  Blood samples collected from 266 cases and 272 controls were subjected to genotyping (PCR amplification of candidate SNPs, RFLP and sequencing). The data on the SNPs were subjected to statistical analysis for assessing the gene frequencies in both the cases and the controls.
  
  
  RESULTS
  The study revealed significant association between the genotypic frequencies of the serotonin receptor polymorphism and schizophrenia. SNP analysis revealed that the frequencies of GG (30%, rs6311) and CC genotypes (32%, rs6313), were higher in patients (P<0.05) than in controls. The study also showed presence of G and C alleles in patients. s0 ignificant levels of linkage disequilibrium (LD) were found to exist between the genotype frequencies of rs6311 and rs6313.
  
  
  CONCLUSIONS
  This study indicated an association between the SNPs (rs6311 and rs6313) of the serotonin receptor 5HT2A and schizophrenia. HapMap analysis revealed that in its genotype distribution, the Tamil speaking population was different from several other populations across the world, signifying the importance of such ethnicity-based studies to improve our understanding of this complex disease.
authors.forename: Subash Padmajeya
authors.initials: SP
authors.lastname: Sujitha
authors.forename: Asha
authors.initials: A
authors.lastname: Nair
authors.forename: Moinak
authors.initials: M
authors.lastname: Banerjee
authors.forename: Srinivasan
authors.initials: S
authors.lastname: Lakshmanan
authors.forename: Sampth
authors.initials: S
authors.lastname: Harshavaradhan
authors.forename: Soosiah
authors.initials: S
authors.lastname: Gunasekaran
authors.affiliation: School of Biosciences & Technology, VIT University, Vellore, India.
authors.forename: Anilkumar
authors.initials: A
authors.lastname: Gopinathan
mesh_terms: D000328:Adult; D005260:Female; D005787:Gene Frequency; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D007194:India; D015810:Linkage Disequilibrium; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D044402:Receptor, Serotonin, 5-HT2A / Q000235:genetics*; D012559:Schizophrenia / Q000235:genetics* / Q000473:pathology; D012701:Serotonin / Q000235:genetics*
chemical_list: D044402:Receptor, Serotonin, 5-HT2A; D012701:Serotonin