title: Genetic association study in nasal polyposis.
abstract: OBJECTIVE
  Nasal polyposis (NP) is a chronic inflammatory disease of the upper airways with a variable clinical course and unknown pathogenesis that often coexists with other conditions. Considering the possibility of genetic predisposition, we decided to analyze whether polymorphisms in LTC4S, CYSLTR1, PTGDR, and NOS2A were associated with NP.
  
  
  METHODS
  The study population comprised 486 Caucasian individuals. Polyposis and aspirin intolerance were diagnosed following the recommendations of the European Position Paper on Rhinosinusitis and Nasal Polyps. Genotypes were determined using polymerase chain reaction amplification and direct sequencing.
  
  
  RESULTS
  The -444A > C LTC4S polymorphism was significantly associated with NP and atopy (P = .033) and with NP and atopic asthma, (P =.012). In addition, a significant association was found when the (CCTTT) repetition of the NOS2A gene was present more than 14 times in patients with NP and asthma (P = .034), in patients with polyposis and intolerance to nonsteroidal anti-inflammatory drugs (P = .009), and in patients with the aspirin triad (P = .005). The PTGDR diplotype CCCT/CCCC (-613CC, -549CC, -441CC and -197TC) was more frequent in patients with NP (P = .043), NP with asthma (P = .013), and the aspirin triad (P = .041).
  
  
  CONCLUSIONS
  NP was associated with specific polymorphisms only when it occurred with related phenotypes. Our results suggest that this genetic background plays a more relevant role in the development of the associated clinical features of nasal polyposis than in simple polyposis.
authors.affiliation: Department of Allergy, University Hospital of Salamanca, Salamanca, Spain.
authors.forename: D
authors.initials: D
authors.lastname: Benito Pescador
authors.forename: M
authors.initials: M
authors.lastname: Isidoro-García
authors.forename: V
authors.initials: V
authors.lastname: García-Solaesa
authors.forename: M
authors.initials: M
authors.lastname: Pascual de Pedro
authors.forename: C
authors.initials: C
authors.lastname: Sanz
authors.forename: L
authors.initials: L
authors.lastname: Hernández-Hernández
authors.forename: J
authors.initials: J
authors.lastname: Sánchez-López
authors.forename: S F
authors.initials: SF
authors.lastname: Lorente
authors.forename: C
authors.initials: C
authors.lastname: Picado
authors.forename: A
authors.initials: A
authors.lastname: Valero
authors.forename: I
authors.initials: I
authors.lastname: Dávila
mesh_terms: D000483:Alleles; D004843:Epistasis, Genetic; D056726:Genetic Association Studies; D005838:Genotype; D006239:Haplotypes; D006801:Humans; D009298:Nasal Polyps / Q000235:genetics*; D052247:Nitric Oxide Synthase Type II / Q000235:genetics; D011110:Polymorphism, Genetic; D020641:Polymorphism, Single Nucleotide
chemical_list: C496319:NOS2 protein, human; D052247:Nitric Oxide Synthase Type II