Objective: The manifestations of BD are considered to have developed as a result of immunological dysfunction, which is suggested to be induced by microbial pathogens. The Toll-like receptor (TLR) genes were known to be associated with a variety of infectious diseases due to their central role in both innate and adaptive immunity. In this report, we investigated the possible association between BD patients and genetic variations within the TLR 2, 4 and 9 genes in a Tunisian population.
Patients and methods: 135 Tunisian BD patients and 159 healthy blood donors from the same geographical area were genotyped by polymerase chain reaction for the TLR polymorphisms.
Results: Among the TLR polymorphisms, only the distribution of TLR9 1486 T/C genotype (p=0.07; chi2=3.30; OR=1.54; 95% CI=0.94-2.51) and allele (p=0.08; chi2=2.91; OR=1.34; 95% CI=0.94-1.92) frequencies was different between BD patients and healthy controls, but did not reach statistical significance. For the TLR9 1237 T/C, the distribution of genotypes and alleles were not significantly different comparing total patients with controls. There were no associations between the studied polymorphisms and the main clinical manifestations of BD. The G, T and A allele of the TLR4 1896 A/G, TLR4 11196 C/T and TLR2 12408 G/A polymorphisms were uncommon and absent in the Tunisian population.
Conclusion: Our results showed that SNPs in the TLR2, 4 and 9 genes were not significantly associated with susceptibility to BD.