<b>Introduction: </b>It is known that in the pathogenesis of tick-borne encephalitis (TBE) various molecules play a significant role. The most prominent factors include IL-10, IL-28B, CD-209 and CCR5. It is reasonable to search for genetic predispositions to the development of various clinical forms of TBE related to the genetic variation of IL-10, IL-28B, CD-209 and CCR5. In this study we aimed to search for the relationship between single nucleotide polymorphism in the promoter region of the CD209, IL-10, IL-28 and 32 base pair deletion in CCR5 coding region (Δ 32) with the human predisposition to development of various clinical presentations of TBE. We tried to assess the relation between the presence of particular alleles and genotypes with laboratory and clinical parameters. <b>Material/Methods </b>59 patients with TBE and 57 people, bitten by a tick who never developed TBE (Polish cohort), were included in the study. To assess the distribution of single nucleotide polymorphisms, TaqMan SNP genotyping assays were used for IL10: rs1800872 and rs1800896, for CD 209 rs4804803 and rs2287886, rs12979860 for IL 28B SNPs according to the manufacturer's protocol using real-time PCR technology on the StepOne thermal cycler. <b>Results </b>Comparison between TBE patients and CG showed that in SNP rs2287886 CD 209 AG heterozygotes were more frequent in the TBE group, while homozygotes GG were more frequent in the CG group. <b>Conclusions </b> SNP rs2287886 CD 209 AG heterozygotes predispose humans to develop TBE. Single nucleotide polymorphism in the promoter region of the CD209, IL-10, IL-28 and CCR5 D32 genes does not correlate with the severity of TBE.
Keywords: CCR5 D32; CD209; IL-10; IL-28; Polymorphism; tick-borne encephalitis.