White supremacists in the US are taking genetic tests to prove their racial identity but are being left bitterly disappointed to learn their genes are not as pure as they presumed.

A new study from the University of California examined years’ worth of posts on Stormfront, a neo-Nazi forum which is the internet’s first major racial hate site, to decipher how members responded to their spit-in-a-cup genetic test results.

White nationalists were up in arms to discover they were not 100 per cent white European and instead had African, Jewish or Asian genes.

The researchers presented their results at a sociology conference in Montreal on Monday just 48 hours after neo-Nazis, KKK members and “alt-right” members clashed with anti-fascists at a white supremacist rally in Charlottesville.

The study found white supremacists would express their indignation at the DNA test results by challenging their veracity and claiming to have a better grip on their genealogy than a scientific test. Some reacted by engaging in racist tirades or arguing the tests were a Jewish conspiracy.

Nevertheless, some of the responses to the tests, which have become increasingly popular among white nationalists, were found to be surprisingly sophisticated and less ignorant than one might imagine.

“If we believe their politics comes from lack of sophistication because they’re unintelligent or uneducated. I think we’re liable to make a lot of mistakes in how we cope with them,” Aaron Panofsky, one of the authors of the report, said.

“For academics, there was some uneasiness around hearing that science is being used in this way and that some of the critiques that white nationalists are making of genetics are the same critiques social scientists make of genetics,” the other author, Joan Donovan, added.

Violence on the streets of Charlottesville Show all 9 1 /9 Violence on the streets of Charlottesville Violence on the streets of Charlottesville Protesters clash and several are injured White nationalist demonstrators clash with counter demonstrators at the entrance to Lee Park in Charlottesville, Virginia. A state of emergency is declared, August 12 2017 Violence on the streets of Charlottesville Trump supporters at the protest A white nationalist demonstrator walks into Lee Park in Charlottesville, Va., Saturday, Aug. 12, 2017. Hundreds of people chanted, threw punches, hurled water bottles and unleashed chemical sprays on each other Saturday after violence erupted at a white nationalist rally in Virginia. AP Photo Violence on the streets of Charlottesville State police stand ready in riot gear Virginia State Police cordon off an area around the site where a car ran into a group of protesters after a white nationalist rally in Charlottesville, Virginia AP Photo Violence on the streets of Charlottesville Militia armed with assault rifles White nationalists, neo-Nazis and members of the 'alt-right' with body armor and combat weapons evacuate comrades who were pepper sprayed after the 'Unite the Right' rally was declared a unlawful gathering by Virginia State Police. Militia members marched through the city earlier in the day, armed with assault rifles. Getty Images Violence on the streets of Charlottesville Statue of Confederate General Robert E Lee The statue of Confederate General Robert E. Lee stands behind a crowd of hundreds of white nationalists, neo-Nazis and members of the 'alt-right' during the 'Unite the Right' rally 12 August 2017 in Charlottesville, Virginia. They are protesting the removal of the statue from Emancipation Park in the city. Getty Images Violence on the streets of Charlottesville Racial tensions sparked the violence White nationalists, neo-Nazis and members of the 'alt-right' exchange insults with counter-protesters as they attempt to guard the entrance to Lee Park during the 'Unite the Right' rally Getty Violence on the streets of Charlottesville A car plows through protesters A vehicle drives into a group of protesters demonstrating against a white nationalist rally in Charlottesville, Virginia. The incident resulted in multiple injuries, some life-threatening, and one death. AP Photo Violence on the streets of Charlottesville Rescue personnel help injured people after a car ran into a large group of protesters after an white nationalist rally in Charlottesville, Virginia AP Photo Violence on the streets of Charlottesville President Donald Trump speaks about the ongoing situation in Charlottesville, Virginia from his golf club in Bedminster, New Jersey. He spoke about "loyalty" and "healing wounds" left by decades of racism.

Mr Panofsky said he found it shocking so many people would post their results on the site despite Stormfront appearing to have strict rules about ethnicity.

“They will basically say if you want to be a member of Stormfront you have to be 100 percent white European, not Jewish,” he told STAT News.

The in-depth study, which was carried out in conjunction with the Data & Society Research Institute, studied comments left in 12 million posts left by more than 300,000 users on Stormfront. The team found 70 discussion threads, where 153 users posted about their DNA results from companies like Ancestry.com and 23andMe with more than 3,000 posts in response.

Stormfront was set up by a former grand wizard of the Ku Klux Klan in the mid-1990s. The name was selected for its obvious connotations of a political or military front such as the Nazi stormtroopers and the Sturmabteilung, which literally translates to Storm Detachment, and was the original paramilitary wing of the Nazi Party.

White supremacists have celebrated President Donald Trump’s response to the deadly violence in Virginia over the weekend which claimed three lives, with one woman killed after a car smashed into a crowd of anti-fascist protesters.

After taking two days to condemn the KKK and neo-Nazi protesters, President Trump eventually gave in to political pressure and sustained criticism and explicitly condemned the actions of white nationalists as “repugnant”.

Nevertheless, he performed a U-turn a day later during a rowdy press conference in Trump Tower, drawing a parity between white supremacists and anti-fascists and saying counter-protesters who he dubbed the “alt-left” were as violent as the KKK and neo-Nazi protesters and the "alt-right" groups included some "very fine" people.

Donald Trump blames both sides for Charlottesville violence

White supremacists hailed Mr Trump’s press conference. Richard Spencer, a leading white supremacist who helped organise the gathering in the quiet university town, took to Twitter to applaud the president “for speaking the truth”.

Former KKK grand wizard David Duke said: “Thank you, President Trump, for your honesty and courage to tell the truth about Charlottesville and condemn the leftist terrorists in BLM/Antifa.”

In the wake of the violence, a KKK leader has said he is happy Heather Heyer, the counter-protester who was killed after a car drove at speed into anti-fascists, had passed away.

Justin Moore, the Grand Dragon for the Loyal White Knights of the KKK, said: "I'm sorta glad that them people got hit and I'm glad that girl died. They were a bunch of Communists out there protesting against somebody's freedom of speech, so it doesn't bother me that they got hurt at all."