Objective: To investigate the association between nasal polyposis (NP) and single nucleotide polymorphisms of the proinflammatory cytokines IL (interleukin) 1alpha (the IL1A gene), IL-1beta (the IL1B gene), and tumor necrosis factor alpha (the TNFA gene).
Design: Prospective case-control trial.
Setting: Tertiary referral center.
Patients: Eighty-two patients with NP and 106 healthy volunteers without sinonasal disease.
Main outcome measures: Genotypes of IL1A (4845G, 4845T), IL1B (-511C, -511T) and TNFA (-238G, -238A and -308G, -308A) were identified by restriction fragment length polymorphism analyses after polymerase chain reaction.
Results: The 4845 GT and 4845 TT genotypes of the IL1A gene were associated with NP (P<.05). The frequency of the -511 CC genotype of the IL1B gene was significantly higher in patients with NP than in controls (P=.01). The frequency of the -511 CT genotype of IL1B was significantly higher (P=.01) in the controls than in the patients with NP. The -238 AA genotype of the TNFA gene was higher in the patients with NP than in the controls (P=.05). There was a significantly high risk of susceptibility to NP in patients with the -308 GA genotype of TNFA (P=.001). None of the genotypes of the proinflammatory cytokines were related to sex, the presence of atopy, asthma, or aspirin intolerance (P>.05).
Conclusion: The IL1A (4845 GT and 4845 TT), IL1B (-511 CC), and TNFA (-238 AA and -308 GA) genotypes were associated with susceptibility to NP in our study population.