Tuesday morning on Fox News, Sen. Lindsey Graham, R-S.C., made an offhand reference to Iranians that’s causing outrage across the internet.

He speculated about the potential outcome of his DNA test, joking, “I’ll probably be Iranian. That would be terrible.”

That comment stems from Sen. Elizabeth Warren, D-Mass., posting a report from a genetics professor that concludes she has Native American ancestry. This has been a controversial topic for years, with President Trump repeatedly questioning her heritage and calling her “Pocahontas.”

My family (including Fox News-watchers) sat together and talked about what they think of @realDonaldTrump’s attacks on our heritage. And yes, a famous geneticist analyzed my DNA and concluded that it contains Native American ancestry. pic.twitter.com/r3SNzP22f8 — Elizabeth Warren (@elizabethforma) October 15, 2018





Following Warren’s release of her report, the Cherokee Nation condemned its political intentions, and, unsurprisingly, Trump wasted no time in criticizing her too.

Thank you to the Cherokee Nation for revealing that Elizabeth Warren, sometimes referred to as Pocahontas, is a complete and total Fraud! — Donald J. Trump (@realDonaldTrump) October 16, 2018





So this morning on Fox and Friends, Graham also waded into the ongoing culture war with a vow of his own.

“I’m going to take a DNA test,” he said. “I have been told that my grandmother was part Cherokee Indian. It may all be just talk, but you’re going to find out in a couple weeks because I’m going to take this test … and the results are going to be revealed here.”

After he made his “terrible” joke about potentially being part Iranian, host Brian Kilmeade tried to sanitize the situation, saying, “They’re great people, just bad leaders.”

It wasn’t long before people on Twitter savaged Graham’s comment, including actor Don Cheadle, who said, “When a Fox News host has to ‘correct’ your racism, you KNOW you’re a racist.”

when a fox news host has to "correct" your racism, you KNOW you're a racist … https://t.co/TiAlWljuZ1 — Don Cheadle (@DonCheadle) October 16, 2018





Many Iranians also responded to Graham. Facebook and Uber investor Hadi Partovi flipped MAGA on its head when he said, “By calling us terrible you insult everything that makes America great.”

Hey @LindseyGrahamSC why is it “terrible” to be Iranian? Some of the greatest businesspeople, scientists, athletes, and leaders in America are of Iranian descent. By calling us terrible you insult everything that makes America great. https://t.co/ByUUlCfGFo — Hadi Partovi (@hadip) October 16, 2018





And Chandra Steele tweeted, “DNA testing showed I’m Iranian and tbh it would be terrible if Lindsey Graham turned out to be anything I am.”

DNA testing showed I'm Iranian and tbh it would be terrible if Lindsey Graham turned out to be anything I am. https://t.co/ektRPFo7jD — (((Chandra Steele))) (@ChanSteele) October 16, 2018





Read more from Yahoo Entertainment: