Grant: Travel Awards - Institute Community Support

Background:Workers in swine operations are exposed to bacteria, virus, and dusts. These exposures have been associated with variable impacts on respiratory health which may be related to variations in individual susceptibility. We investigated the effects of polymorphisms in the Toll-Like Receptor 2 (TLR2) and Toll-Like Receptor 4 (TLR4) genes on lung function in workers from swine operations and non-farming controls. Methods:374 full-time workers from large swine operations and 411 non-farming rural dwellers were chosen for the study. Information on demography, lifestyle and occupation was collected using a questionnaire. Pulmonary function measurements and blood samples were also obtained. Differences in the lung function parameters between different genotypes of each SNP in the TLR2 and TLR4 genes were estimated after controlling for age, sex, height, weight and smoking habit using multiple linear regression techniques. Results:Workers with TLR2 polymorphisms, Thr399Ile (AG), Arg677Trp (CT or TT) and Arg753Ile (AA) had significantly greater mean values of FEV1, FEV1/FVC ratio and FEF25%-75% than workers with wild-type for the three SNPs, respectively, after controlling for age, sex, height, weight, and smoking habit. No significant differences were observed in the mean values of lung function parameters between the polymorphism and wild-type groups of the three SNPs in the TLR2 gene among non-farming controls. For the TLR4 gene, there were no significant differences in the mean values of lung function parameters between the polymorphic (AG or GG) and wild-type (AA) groups of Asp299Gly polymorphism and between the polymorphic (CT) and wild-type (TT) groups of Thr399Ile polymorphism in workers in the swine operations or non-farming controls. Conclusions:Our study is the first to report the respiratory health effects of TLR2 polymorphisms among workers in swine operations. TLR4 polymorphisms appeared to be of less importance in this population than TLR2.