One in three North Korean refugees from nuclear test area have mutations

One in three North Korean refugees hailing from a nuclear test area have chromosomal mutations, a new study has found. 

According to research conducted by South Korea's unification ministry, the genes of 64 out of 214 North Korean defectors tested showed genetic changes potentially tied to radiation. 

An official at the National Radiation Emergency Medical Centre, which conducted the five-year study, said it was scientifically reasonable to suspect the tests at the Punggye-ri site in the North Hamgyong province were the cause of these mutations. 

The latest series of the medical tests were conducted last year, and showed that 26 out of 59 North Koreans who lived in eight cities and counties near Punggye-ri had chromosomal abnormalities - roughly 40%. 

The ministry shared the new report with South Korea's National Assembly - the country's parliament - but cautioned that there may be environmental factors at play. 

Researchers called for more tests to be run to establish a clearer link with the nuclear tests. 

They are aiming to recruit 50 new participants, as well as 10 returning subjects for follow-ups, in this year's tests.  

So far, around 800 North Koreans from the eight cities and counties around Punggye-ri have resettled in South Korea. 

Punggye-ri was reportedly closed down in 2018 by the North Korean government, in what it said was a measure to 'ensure the transparency of discontinuance of nuclear tests.'

It was there that North Korea performed its first nuclear test in 2006. Researchers still aren't sure whether a successful test on a particularly small nuclear device, or a 'fizzle' of an ordinary one, was carried out. 

Several more were carried out over the years, with two tests taking place in 2016. 

In 2017, there was a collapse at the site that was estimated to have left 200 workers dead. 

South Korean officials warned after the collapse that further nuclear tests at Punggye-ri could cause a nearby mountain to crumple, releasing radioactive material into the environment. 

And Chinese officials warned that the nuclear fallout could spread across 'an entire hemisphere' if the mountain caved in. 

The dismantling of the nuclear test ground 'completely closed the tunnel entrances', the government's mouthpiece KCNA reported, adding that two tunnels there had been ready for use in 'powerful underground nuclear tests.'

And analysts observed in 2022 that the site was being rehabilitated for potential nuclear cruise missile warhead tests. 

The US, South Korea and Japan said at the time that North Korea would receive an 'overwhelming, decisive... and unparalleled' response if testing was resumed.