Chemical markers on DNA help to reveal divergence in cattle immune systems between breeds and potential for improving disease resistance. Image Researchers have revealed important variations in chemical markers found attached to DNA that likely influence gene activity in the immune systems of cattle. The study of changes in these chemical markers, known as epigenetics, across cattle populations can aid in understanding how their immune systems are regulated. Findings in the study led by Roslin scientists indicated extensive divergence in these markers in immune cells of different cattle subspecies, suggesting that they may influence how cattle immune responses differ. These results have important implications for enabling research that is representative of global cattle populations, researchers suggest. The findings could inform efforts to improve livestock disease resistance. Open access database The Roslin and Royal (Dick) School of Veterinary Studies team created datasets that include 150 samples derived from immune cells belonging to three different cattle breeds in the UK, Kenya and Brazil. The data were compiled in an online public database, where scientists can access it for future studies. Researchers tested a method to work out the proportion of different immune cell types in blood samples, based on the chemical markers found on DNA. They did so by looking at chemical markers that are unique to certain cell types. These markers do not affect the DNA sequence, but can affect how genes work by turning them on or off. The research team used four different technologies to analyse markers of immune cells in different cattle breeds to help them understand how and where these markers vary. Although existing research has identified underlying genetic differences between cattle breeds, little is currently known about these chemical modifications to the DNA, which may be responsible for differences in their immune response. This research was published in Genome Biology and funded by an EASTBIO PhD studentship, the UK Biotechnology and Biological Sciences Research Council, and the Bill & Melinda Gates Foundation and the UK Foreign, Commonwealth and Development Office under the auspices of the Centre for Tropical Livestock Genetics and Health (CTLGH). The chemical modifications that can influence gene activity without changing the DNA sequence are largely understudied in cattle, especially in non-European breeds. Understanding the variation between cattle which respond well or poorly to infections will be essential for selective breeding of animals with improved disease resistance. Dr Jess Powell, Core scientist post-doctoral research fellow, Roslin Institute and Royal (Dick) School of Veterinary Studies ** The Roslin Institute receives strategic investment funding from the Biotechnology and Biological Sciences Research Council and it is part of the University of Edinburgh’s Royal (Dick) School of Veterinary Studies. ** Related links Scientific publication Open access data set Image credit: Jakob Cotton/ Unsplash
