associations of toll-like receptor 7 and 8 polymorphisms with asthma and asthma-related phenotypes in a chinese han population

toll-like receptor (tlr) 7 and 8 mediate anti-virus immunity and are of particular relevance to asthma. however, very little information about genetic association on tlr7/8 and asthma are available. this study aimed to evaluate the effects of polymorphisms in tlr7 and 8 on asthma risk and asthma-related phenotypes in a chinese han population. we enrolled 462 unrelated adult asthmatic patients and 398 healthy volunteers. the genotypes of tagging single nucleotide polymorphisms (snps) in tlr7 and 8 genes were determined using multiplex snapshot snp genotyping assay. we used case-control and case-only studies to assess any links with asthma and asthma-related phenotypes. there was no association between the variants in tlr7 and 8 and asthma susceptibility. however, our results revealed that the genetic variants in tlr7 and 8 were associated with asthma-related phenotypes, including eosinophil counts, serum immunoglobulin e levels, lung function, and asthma severity as well. our study suggests that tlr7 and 8 polymorphisms may play a considerable role in the pathogenesis of asthma. it will help in better understanding the pathogenesis of asthma and development of more effective strategies for asthma prevention, prediction, and therapy.