Ancient variant clue to Indigenous respiratory illness

A breakthrough discovery has revealed an ancient gene variant influencing immune defences among Aboriginal and Torres Strait Islander people.

The ancient variant of the natural killer receptor was identified by researchers from the Peter Doherty Institute, Monash University, Menzies School of Health Research, University of Colorado and Stanford University.

Natural killer cells are a type of white blood cell key in mediating early immune control against a broad range of viruses, Doherty Institute professor Katherine Kedzierska said.

These cells can restrict viruses from replicating in early stages of infection, which means they play an important role in the ability to prevent infection and recover from a virus.

Indigenous people are at higher risk of severe respiratory viral diseases, including influenza and COVID-19, Professor Kedzierska said.

The study provides a new understanding of immune response among people from across Oceania including Australasia, Melanesia, Micronesia and Polynesia.

"Indigenous people globally also have increased influenza, pneumonia hospitalisation rates," Prof Kedzierska told AAP.

"In addition to social and health determinants, the immune cells and especially genetic variations within immune cells may contribute to increased risk of respiratory diseases."

The researchers conducted in-depth genomic and molecular analysis of natural killer cells in Indigenous people, at the Stanford University genomic facility and the Australian Synchrotron.

About 200 'flavours' or types of natural killer cells exist in the body, the institute's Andrew Brooks said.

"What we've identified is a variant that changes the flavour, or the type of response, essentially that the NK (natural killer) cells can make in the Indigenous population," Professor Brooks said.

"It probably enhances the capacity response to some things and it probably detracts capacity response to other things."

The natural killer variant identified by the research team appears to be exclusive to the people of Oceania.

Analysis of more than 1300 individuals revealed the frequency of this variant was as high as 28 per cent among highland Papuans, and about six per cent in Indigenous people from northern Australia, Prof Kedzierska said.

Findings of the study could inform the design of new vaccines and immunotherapies.

"Understanding of immune responses in First Nations people globally is really important because immunological genetic studies do not often involve First Nations people and other minority populations," she said.

"Our study really reveals the importance of working with First Nations people to understand immune responses and how we can protect everyone from severe infectious diseases, including respiratory viral infections."

The research has been published in the journal Cell.