A reduced incidence of digestive disorders in rabbits is associated with allelic diversity at the TLR4 locus

Toll-like receptor 4 (TLR4) plays a fundamental role in pathogen recognition and activation of host innate immunity. In this study, we detected five coding single-nucleotide polymorphisms (cSNPs) of the TLR4 gene in New Zealand White rabbits and analyzed their associations with genetic resistance against digestive disorders based on case–control study (125 cases and 147 controls). The five cSNPs included two synonymous mutations (c.57 C > T and c.1098 G > A) and three non-synonymous mutations (c.566 G > A, c.760 G > A, and c.923 A > G), which totally determined two alleles (haplotypes) H1 (the five cSNPs: CGGAG) and H2 (the five cSNPs: TAAGA) with pair-wise LD (D′) estimates of 1.0. The frequencies of alleles and genotypes significantly differed between case group and control group (P < 0.05). The association analyses revealed that allele H2 carried a potential protective role with an odds ratio (OR) value of 0.521 (95% confidence interval 0.324–0.837, P = 0.0064). To our knowledge, this is first report to study the genetic polymorphism of TLR4 gene and association with incidence of digestive disorders in rabbits.