title: The serotonin transporter promoter polymorphism (5-HTTLPR) is associated with type 2 diabetes.
abstract: BACKGROUND
  The serotonergic system contributes substantially to the regulation of glucose homeostasis and feeding. 5-HTTLPR is a serotonin transporter (5-HTT) gene-linked polymorphic region that regulates the transcriptional activity of 5-HTT. Our aim was to investigate the possible association of 5-HTTLPR polymorphism with type 2 diabetes mellitus and obesity.
  
  
  METHODS
  Study population consisted of 252 subjects diagnosed with Type 2 DM and 211 non-diabetic subjects, all Caucasians of Greek ethnic origin. Genomic DNA was extracted from peripheral blood and analyzed for 5-HTTLPR polymorphism with a novel PCR protocol.
  
  
  RESULTS
  The frequency of SS and SL genotypes of HTTLPR was significantly higher in the diabetic group (77.0%) than in the non-diabetic group (61.6%) (P<0.001). The genetic risk of Type 2 DM for subjects carrying at least one S allele was increased compared to non-diabetic subjects (OR=2.08, 95% CI=1.39-3.12). When subjects were divided according to BMI status, the frequency of S allele carriers was similar in obese and non-obese subjects.
  
  
  CONCLUSIONS
  The S allele of 5-HTTLPR is strongly associated with the presence of Type 2 DM. This association appears to be direct and not dependent on obesity status. Therefore, 5-HTTLPR LL genotype might be protective for development of Type 2 DM.
authors.affiliation: Laboratory of Pharmacology and Clinical Pharmacology, Medical School, Democritus University of Thrace, Dragana Campus, 68100 Alexandroupolis, Greece.
authors.forename: Maria
authors.initials: M
authors.lastname: Iordanidou
authors.forename: Anna
authors.initials: A
authors.lastname: Tavridou
authors.forename: Ioannis
authors.initials: I
authors.lastname: Petridis
authors.forename: Kostas I
authors.initials: KI
authors.lastname: Arvanitidis
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Christakidis
authors.forename: Vassilios
authors.initials: V
authors.lastname: Vargemezis
authors.forename: Vangelis G
authors.initials: VG
authors.lastname: Manolopoulos
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D016015:Logistic Models; D008297:Male; D009765:Obesity / Q000150:complications / Q000235:genetics; D011110:Polymorphism, Genetic; D011401:Promoter Regions, Genetic / Q000235:genetics*; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics*; D044465:White People / Q000235:genetics
chemical_list: C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins