Genetic polymorphisms within the TLR4 gene have been reported to be associated with various inflammatory diseases; therefore, TLR4 appears to be a susceptibility gene for sarcoidosis.
In conclusion, genotype data for the TLR4Asp299Gly and Thr399Ile polymorphisms in the Greek population were found to be in linkage disequilibrium, and no contribution in the pathogenesis of sarcoidosis was established.
In the subgroup of patients with acute sarcoidosis there was no difference in the control group (P = 0.93), but there was a highly significant association between patients with a chronic course of sarcoidosis and TLR4 gene polymorphisms (P = 0.01).
Recently, an association between TLR-4 polymorphism Asp299Gly, leading to a change in the extracellular domain of the receptor and possible hyporesponsiveness to LPS, and a chronic course of sarcoidosis was found in German patients.