TLR-2 gene Arg753Gln polymorphism is strongly associated with acute rheumatic fever in children.
The recently described family of toll-like receptors (TLRs) is a key player in host immunity by mediating inflammatory reactions against a wide range of pathogens. Mutations and polymorphisms in TLRs have revealed the importance of TLRs in human defence against diseases. TLR-2 is reported to interact with different bacterial structures, including lipoproteins, peptidoglycan and lipoteichoic acid. To assess the role of TLR-2 gene polymorphism in acute rheumatic fever (ARF) etiopathology, 61 independent Caucasian Turkish patients and 91 child and 116 adult controls were studied. Antistreptolycin O, C-reactive protein, sedimentation and white blood cell counts were studied to evaluate the clinical characteristics of the patients. Genomic DNA was extracted from peripheral blood using a standard column extraction technique. The Arg753Gln and Arg677Trp polymorphisms were genotyped by polymerase chain reaction (PCR) restriction fragment length polymorphism. The PCR products for the TLR-2 gene were analysed on 1.5% agarose gel pre-stained with ethidium bromide. Compared with healthy adult controls, the Arg753Arg genotype was significantly decreased in the entire group of ARF cases [odds ratio (OR) 0.01, 95% confidence interval (95% CI) 0.0034-0.031, p<0.0001]. Significantly, ARF patients were just 16 times more frequent with Gln allele (OR 15.6, 95% CI 7.87-30.8, p<0.0001). Moreover, evidence for an intensifying effect of the Gln allele was noteworthy when patients with Arg753Gln genotype were compared with healthy controls (OR 97.1, 95% CI 32.5-290, p<0.0001). However, no Arg677Trp polymorphism was detected in either patients or controls. Our data suggest that there is strong evidence for the biological role of TLR-2 in ARF. The common TLR-2 Arg to Gln polymorphism at position 753 significantly contributes to the pathogenesis of ARF. These results will allow the construction of a profile of individuals prone to ARF and may assist in developing new therapies.
Berdeli
Afig
A
Laboratory of Molecular Medicine, Department of Pediatrics, Ege University School of Medicine, Bornova, Izmir, 35100, Turkey. afig@med.ege.edu.tr
Celik
Handan Ak
HA
Ozyürek
Ruhi
R
Dogrusoz
Buket
B
Aydin
Hikmet Hakan
HH
D000328:Adult; D016022:Case-Control Studies; D002648:Child; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005838:Genotype; D006801:Humans; D008297:Male; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D012213:Rheumatic Fever / Q000235:genetics*; D051195:Toll-Like Receptor 2 / Q000235:genetics*; D014421:Turkey; D044465:White People / Q000235:genetics
C495342:TLR2 protein, human; D051195:Toll-Like Receptor 2