SUSCEPTIBILITY TO PARATUBERCULOSIS IS ASSOCIATED WITH SINGLE NUCLEOTIDE POLYMORPHISMS IN BOVINE TOLL-LIKE RECEPTOR 2

摘要

Paratuberculosis is a chronic intestinal infection in ruminants, caused by Mycobacterium avium subspecies paratuberculosis (Map). To study the role of host genetics in disease susceptibility the Toll-like receptor 2 (TLR2) gene, selected based on itspotential role in immunity to mycobacterial infections, was analysed for single nucleotide polymorphisms (SNP) and disease association. Sequence analysis of the TLR2 gene and SNP discovery in a case-control study with 12 paratuberculosis infected animals, and 12 age-matched healthy herd-mates, revealed 21 different SNP. The TLR2-1903T/C SNP was significantly associated with resistance to Map. The allelic distribution of the TLR2-1903T/C SNP was subsequently confirmed to be significantly different between the infected and non-infected animals in a cohort study with 553 cows from farms with paratuberculosis. In conclusion, this study identified genetic polymorphisms in bovine TLR2 which are associated with susceptibility to paratuberculosis in the DutchHolstein-Frisian cattle population.