title: Relationship of obstructive sleep apnea syndrome with the 5-HT2A receptor gene in Brazilian patients.
abstract: BACKGROUND
  Serotonin (5-HT) regulates a variety of visceral and physiological functions, including sleep. Polymorphisms in the 5-HT2A receptor gene can alter its transcription, affecting the number of receptors in the serotoninergic system, contributing to obstructive sleep apnea syndrome (OSAS).
  
  
  OBJECTIVE
  The aim of this study was to determine the prevalence of the 102T-C and -1438G-A polymorphisms in the 5-HTR2A gene in Brazilian patients with and without OSAS.
  
  
  METHODS
  A cross-sectional study performed at the Otorhinolaryngology and Sleep Disorder Out Clinics, São José do Rio Preto Medical School, FAMERP. One hundred patients were examined as index cases and 100 persons as controls, of both genders to both groups. DNA was extracted from peripheral blood leukocytes, and the sites that encompassed both polymorphisms were amplified by PCR-RFLP.
  
  
  RESULTS
  There was a significant prevalence of the male gender in index cases compared with the control group gender (p < 0.0001). There was no significant genotypic difference in the 102T-C polymorphism between the case and control groups (p = 1.000). The AA genotype of the -1438G-A polymorphism was more prevalent in the patients with OSAS compared with the controls (OR, 2.3; CI 95% 1.20-4.38; p = 0.01).
  
  
  CONCLUSIONS
  There was no difference in the prevalence of the 102T-C polymorphism between patients with OSAS and the control group. Serotoninergic system dysfunction appeared to be related to OSAS. The -1438G-A polymorphism and OSAS are related in this studied Brazilian population.
authors.affiliation: Department of Otorhinolaryngology and Sleep Disorder Out Clinics, São José do Rio Preto Medical School, São Paulo, Brazil.
authors.forename: Thiago Bittencourt Ottoni
authors.initials: TB
authors.lastname: de Carvalho
authors.forename: Marcela
authors.initials: M
authors.lastname: Suman
authors.forename: Fernando Drimel
authors.initials: FD
authors.lastname: Molina
authors.forename: Vânia Belintani
authors.initials: VB
authors.lastname: Piatto
authors.forename: José Victor
authors.initials: JV
authors.lastname: Maniglia
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000403:Airway Resistance / Q000235:genetics / Q000502:physiology; D000483:Alleles; D001938:Brazil; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length / Q000235:genetics*; D044402:Receptor, Serotonin, 5-HT2A / Q000235:genetics* / Q000502:physiology; D012701:Serotonin / Q000502:physiology; D020181:Sleep Apnea, Obstructive / Q000453:epidemiology / Q000235:genetics* / Q000503:physiopathology; D014158:Transcription, Genetic / Q000235:genetics; D055815:Young Adult
chemical_list: D044402:Receptor, Serotonin, 5-HT2A; D012701:Serotonin