Genetic discovery could help defeat deadly African cattle infection

A piece of DNA found to protect native African cattle from East Coast fever could protect breeds introduced to the region.

Scientists have identified a key stretch of DNA that allows certain types of cattle to survive a potentially devastating infection, making it more likely to breed disease-resistant cattle.

“The discovery of the genes that allow cattle to survive East Coast Fever infection opens the way for this beneficial DNA to be introduced into non-native breeds, reducing disease and increasing productivity, which will benefit millions of small rural farmers in Africa,” said Dr. James. Prendergast of the Roslin Institute and the Center for Tropical Livestock Genetics and HEALTH.

The discovery could help fight East Coast fever, or theileriosis, which kills a million animals every year and costs farmers $600 million , mostly affecting smallholders in sub-Saharan Africa.

This could allow farmers in affected regions of Africa to keep non-native breeds with higher productivity if they carry the necessary genomic traits to carry the disease.

The discovery provides an opportunity to tackle the growing threat of the brown ear mite, which spreads the infection-causing parasite Theileria parva.

Researchers at the Center for Tropical Livestock Genetics and Health (CTLGH), the Roslin Institute, the International Animal Research Institute (ILRI) and the University of Glasgow have tried to understand whether cross-generational sections of the bovine genome can help some animals survive infection. caused by East Coast fever.

Genetic analysis of Boran cattle, an East African breed that can carry the disease, has led the team to identify a region of DNA that may play a key role in preventing the deadly infection. The team confirmed their findings using data previously obtained from an independent population of East African cattle. Their results suggest that the region of DNA isolated in their study could have evolved in response to another Theileria parasite known as Theileria annulata and could potentially provide protection against both.

The result suggests that breeding cattle that are DNA-edited to introduce the necessary genetic signature could increase tolerance to East Coast fever in imported cattle in Africa.

“This groundbreaking study, which aims to identify genes that could change how cattle are raised for small farmers in low- and middle-income countries, is an example of an effective partnership between British and African experts in genomics and livestock breeding to find practical solutions to increase productivity,” said Professor Appolinaire Jikeng of the Center for Tropical Livestock Genetics and Health.

The study, published in PLOS Genetics, was funded by the Bill & Melinda Gates Foundation and the UK Foreign, Commonwealth and Development Office (FCDO) and supported by CGIAR and the Biotechnology and Life Sciences Research Council of UK Research and Innovation.