Novel DNA test to accurately identify WWII soldiers

Scientists have developed a novel DNA test for missing soldiers from historic battles, that may help accurately identify casualties from World War II.

More than 25,000 Australian soldiers who made the ultimate sacrifice have no known grave, and thousands of those are in the Asia-Pacific area, according to the researchers from Queensland University of Technology (QUT) in Australia.

Forensic biologist Kirsty Wright, who works with the Australian Defence Force identifying victims of current conflicts and disasters, said historic cases are extremely challenging because often only a few bone fragments are found, and the remains can be highly degraded due to decades of exposure to the elements.

"This is particularly the case in the Asia-Pacific area, where in 95 to 99 per cent of cases we have only partial remains," said Wright.

"We often have no other forensic evidence to work from, and limited artefacts such as badges or identity tags that might provide some clues," she said.

Wright said the first step was to determine ancestral origin.

For example, on the Kokoda Track or in the jungles of Papua New Guinea, the remains found may belong to an Australian or Japanese soldier or may even be of local origin. Ensuring respectful association and likely origin is a top priority.

"The current utilised method is from modern criminal investigation case work and uses mitochondrial DNA, following maternal lineage," Wright said.

"However in 69 to 83 per cent of these historical cases current DNA tests can't reliably identify ancestry," she said.

Researchers developed a targeted SNP panel to identify ancestral origins of Australian and Japanese WWII soldiers. SNPs have become a commonly used genetic marker for ancestry.

The panel also includes genetic variation information on hair and eye colour as an extra layer of identification.

"It is very important to be confident with ancestral origin so that, for example, Japanese soldiers can be returned with honour to the Japanese government," Wright said.

"Once we establish that we have found an Australian soldier, the Unrecovered War Casualties - Army unit can then move to the next stage of giving the soldier back their name, and bringing closure to the family," she added.

Wright said to test the accuracy of the new SNP panel, researchers in the team generated profiles of Australians born around World War II, and used profiles of people from Japan.

"We were pleased to get 100 per cent accuracy with the test predicting Australian and Japanese ancestry," Wright said.

"Based on the population samples we also found that the SNP test identified ancestry in 79 per cent more cases than currently used DNA methods," she said.