Cytokine gene polymorphism in recurrent acute otitis media.

BACKGROUND There is increasing evidence that a strong genetic component is involved in the predisposition to recurrent acute otitis media (rAOM). Cytokines play a key role in the pathogenesis of otitis media. Constitutional polymorphisms in cytokine genes may lead to individual variations in cytokine secretion. OBJECTIVE To elucidate the role of cytokine gene polymorphisms in rAOM. SETTING University hospital. PARTICIPANTS AND METHODS Blood samples for genetic analysis were obtained from 63 individuals with rAOM from 20 different families and from 400 healthy blood donors. The medical history of the rAOM group was based on medical records and interview data. We studied the polymorphisms of tumor necrosis factor alpha, interleukin (IL) 1 alpha, IL-1 beta, and IL-1 receptor antagonist genes. RESULTS The distribution of cytokine alleles in the rAOM group did not differ significantly from that of the control group. However, in patients with rAOM without a history of allergic disorders, allele frequencies of IL-1 alpha-889 differed significantly from those of controls (P =.03). CONCLUSIONS There is no clear association between the polymorphism of studied cytokine genes and rAOM. However, the IL-1 alpha gene polymorphism may be associated with recurrent middle ear infections in a subgroup of patients without allergic disorders.