Interleukin-10 Gene Polymorphisms and Susceptibility to Brucellosis in Iranian Patients

Background: Interleukin-10 (IL-10) is a Th2-type cytokine that inhibits macrophage activation. It is known that production of IL-10 is affected by its gene promoter poly-morphisms. Objective: To investigate the relationship between IL-10 gene promoter polymorphisms and susceptibility to brucellosis. Methods: One hundred and ninety pa-tients with brucellosis and 81 healthy animal husbandmen who owned infected animals and consumed their contaminated dairy products were included in this study. All indi-viduals were genotyped for three bi-allelic IL-10 gene promoter polymorphisms at posi-tions -1082(G/A), -819(T/C), and -592(A/C) using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Results: The distribution of C alleles at positions -592 and -819 of IL-10 were significantly higher in patients than in the healthy animal husbandmen (p=0.034 and p=0.0086, respectively). IL-10 ATA single and dou-ble haplotypes were significantly higher in controls, compared to the patients (p= 0.0278 and p=0.013, respectively). Conclusion: According to the results higher fre-quency of C alleles at positions -592 and -819 of IL-10 in patients may be considered as genetic factors for susceptibility to brucellosis.