Disease resistance gene pinpointed in farmed salmon, trout
Using a combination of genomics and gene-editing technologies, a team of scientists has identified a gene that has a major role in the resistance of salmonids to Infectious Pancreatic Necrosis Virus (IPNV), a disease that can cause high mortality levels in farmed salmon and trout.
The study, carried out by the Roslin Institute and Hendrix Genetics – together with the University of Stirling; the Centre for Environment, Fisheries and Aquaculture Science; and Uppsala University – identified the gene Nedd8 Activating Enzyme E1 (Nae1) in Atlantic salmon using CRISPR gene-editing technology.
According to the researchers, the finding provides insight into why some salmon are resistant and others are susceptible to IPNV, and could lead to more accurate selection of breeding fish. That in turn would contribute to ongoing successful disease control, using a process known as marker-assisted selection, in salmon farming.
Personal Chair of Aquaculture Genetics at the Roslin Institute Professor Ross Houston, said the control of IPNV using marker-assisted selection in salmon breeding has led to a marked reduction in outbreaks, saving millions of salmon per annum.
“The discovery of a gene underlying this effect may facilitate more accurate selection, and also open the door to possible future avenues of disease control in strains or species where the marker-assisted selection is not possible,” he said.
Researchers also used gene-editing to remove the Nae1 gene from salmon cells and, in separate experiments, used chemical methods to prevent the Nae1 enzyme formed by the gene from functioning in salmon cells. In both cases, limiting the function of Nae1 in cells that were exposed to the virus led to a significant drop in replication of the virus in those cells.
“With genetics we are able to support the global food challenge,” Hendrix Genetics Chief Innovation & Technology Officer Johan van Arendonk said. “Genetic technologies like gene editing and marker assisted selection offer ways to innovate or accelerate sustainable solutions. Disease threats are still one of the major challenges of any protein value chain and finding ways to fight these will help us to set new standards for sustainable animal breeding.”
Photo courtesy of British Columbia Salmon Farmers Association