Risk haplotype analysis for bovine paratuberculosis.

Paratuberculosis (Johne's disease), caused by Mycobacterium avium subsp. paratuberculosis, is an important disease for bovines, although its genetic basis is poorly understood. In this study, three candidate genes were typed to study the associations between single nucleotide polymorphisms (SNPs) and paratuberculosis susceptibility (measured in a 1 or 0 form) at the haplotype level. A significant risk haplotype, constructed by a variant allele (C) at the first SNP and a common allele (A) at the second SNP, within the CARD15 gene was detected to trigger genetic effects on paratuberculosis infection in an overdominace manner. Marginally significant haplotypes were identified for the other two genes. The results obtained will provide scientific guidance about the selection and prediction of resistance types in bovines.