DNA study could help breed virus-resistant poultry

Friday 8th July 2022, 6:00pm

Analysis of chicken genes by a team of scientists from the Roslin Institute has highlighted possible variants linked to innate immunity against damaging viral infections.

Chicks - credit University of Edinburgh

Poultry could be bred to resist damaging viral infections, following a study of genes linked to chicken immunity.

A study of different types of chickens – known to be either more resistant or more susceptible to common poultry viruses – has uncovered dozens of variations in genes with a central role in the chicken immune response to infection.

The findings may point to genetic variations that determine birds’ response to infection, to help breed poultry that are resistant to disease.

Researchers analysed DNA from chickens that have been found to be naturally more resilient or prone to bird flu, Marek’s disease, infectious bursal disease, or infectious bronchitis virus, all of which are costly viruses for the poultry industry. Computer analysis looked for variations in the genes linked to production of immune proteins known as interferons, and other associated molecules.

The team sought to compare their findings with a standard reference genome for chickens, to determine the effect caused by variations in these regions of DNA and how they might be associated with each bird’s response to infection. In all, their analysis highlighted 60 genetic variations that are likely to influence resistance or susceptibility to one of the four infections.

"Viral infections are a significant challenge for the poultry industry as well as impacting on animal welfare. Determining genetic factors that enable birds to present a robust resistance to infection could deliver a host of benefits."

Joshua Mountford, Study lead author, the Roslin Institute

Further research could involve testing the impact of these DNA variations on chicken cells and exposing these to each of the four viruses in the lab, to better understand the mechanisms involved. This could help determine which genetic variations could be bred into chickens to enable the birds to resist viral infection. The discovery could also inform research into drug design or vaccine improvement to protect poultry against infection.

This may also have relevance for immunity in people, as the human immune system has similar processes to those investigated in this study, and viruses such as avian flu also have the potential to transmit to humans.

"Our study is a good first step to understand the genetic factors influencing innate immunity to a range of viral infections in poultry. The variants we have discovered merit further investigation and could be valuable in breeding chickens resistant to disease."

Dr Jacqueline Smith, the Roslin Institute

Article source:  Roslin Institute