Genome-wide association study identifies novel loci associated with resistance to bovine tuberculosis

Tuberculosis caused by Mycobacterium bovis is a re- emerging disease of livestock which is of major economic importance world-wide, as well as being a zoonotic risk. There is significant heritability for host resistance to bovine tuberculosis (bTB) in dairy cattle. To identify resistance loci for bTB, we undertook a genome-wide association study in female Holstein-Friesian cattle with 592 cases and 559 age-matched controls from case herds. Cases and controls were categorised into distinct phenotypes: skin test and lesion positive versus skin test negative on multiple occasions, respectively. These animals were genotyped with the Illumina Bovine HD 700K bead chip. Genome-wide rapid association using linear and logistic mixed models and regression (GRAMMAR), regional heritability mapping (RHM) and haplotype-sharing analysis identified two novel resistance loci that attained chromosome-wise significance, in protein tyrosine phosphatase receptor T (PTPRT; P=4.8 x 10-7) and myosin IIIB (MYO3...