Association of TLR2 gene Arg753Gln polymorphism with urinary tract infection in children.

The aim of this study is to investigate Arg753Gln allele polymorphisms of toll-like receptor-2 (TLR2) gene distribution, allele frequency in urinary tract infection (UTI) and genotype-phenotype association of TLR2 gene in children with UTI. The polymorphism was investigated in 124 children with UTI (22 boys and 102 girls; mean age 5.81 +/- 3.47 years) with direct DNA sequencing-based method. TLR2 gene Arg753Gln allele frequency was higher in the patient group when compared with control group (OR 3.14, 95%CI 1.53-6.44, P < 0.001). The frequency of the Arg753Gln allele was significantly higher in gram-positive group than in gram-negative group (OR 7.64, 95%CI 2.80-20.81, P < 0.001). The frequency of UTI was found significantly higher in the Arg753Gln allele carriers of TLR2 gene than the non-carriers (OR 4.94, 95%CI 1.09-22.33, P < 0.05). Similarly, the incidence of asymptomatic UTI was also found significantly higher in the group carrying Arg753Gln allele (OR 3.73, 95%Cl 1.54-9.04, P < 0.05). As a result, we suggest that TLR2 gene could be the predisposing factor for urinary tract infection. Additionally, we observed that subjects carrying the TLR2 Arg753Gln allele had higher risk of urinary tract infection with gram-positive pathogens, history of more than two attacks of UTI and asymptomatic UTI.