Relationship between toll-like receptor 2 R753Q and T16934A polymorphisms and Staphylococcus aureus nasal carriage

The association among specific single-nucleotide polymorphisms (SNPs) in TLR2 R753Q (rs5743708) and T16934A (rs4696480) and the nasal carriage of Staphylococcus aureus was studied in adults before CABG.

The TLR2 polymorphisms were genotyped in 299 consecutive patients prepared for a CABG operation. Genotyping was performed using restriction fragment length polymorphism (RFLP) analysis of PCR-amplified fragments. Two nasal swab cultures were taken within 2 weeks before the operation. Subjects were classified as Staphylococcus aureus carriers if at least one culture was positive while those patients with both cultures found to be negative were classified as non-carriers.

The prevalence of nasal S. aureus carriage in the final cohort was 22.1% (66/299), while no MRSA was detected in our study group. No significant differences in the TLR2 polymorphisms were observed between the study and the control groups. No associations were found between TLR2 haplotypes and the covariates of age, sex, NYHA, weight, height, BMI, CAD, smoking status and ESlog score. No differences were found between carriers and noncarriers regarding the allelic distribution of the TLR2 T-16934A SNP. Almost 93% of the patients who were screened for the presence of the TLR2 Arg753Gln (rs5743708) were GG wild type homozygous. Twenty one subjects from the study group (7.1%) were GA heterozygous, while no patient in either group was homozygous for the TLR2 Arg753Gln (rs5743708) mutation. TLR2 Arg753Gln genotyping showed that GA heterozygous patients were detected more frequently in the group of Staphylococcus aureus nasal carriers than in non-carrier adults.

Our results suggest that the carrier status for the GA variant of the TLR2 Arg753Gln (rs5743708) polymorphism may be a risk factor for Staphylococcus aureus carriage.