Aisha Fong's MSc Defence

Johne’s disease is a chronic wasting disease in dairy cattle caused by the bacterium Mycobacterium avium subspecies paratuberculosis (MAP). Genetic selection can help to control this disease, and one candidate gene of interest is the gene encoding for interleukin-10 receptor subunit alpha (IL10Rα). A bovine mammary epithelial cell line was created with the gene encoding IL10Rα knocked out (IL10KO). This cell line was ex-posed to live MAP, and mRNA was extracted. The differentially expressed genes were compared between the IL10KO and wild-type cell lines, and gene ontology was performed. There was a difference in immune response between the IL10KO and wild-type cells, and little difference between the uninfected IL10KO cells and the infected IL10KO cells. Haplotypes 0.5Mb upstream and downstream of IL10Rα associated with a positive test for Johne’s disease were not found within a population of 618 cows, however there was genetic variation, meaning there is potential for selection.