How Kal Penn ended up tattooing the wrong DNA ancestry result on his arm

One of Kal Penn's tattoos was supposed to represent his heritage, but it didn't quite turn out the way he planned.

During an appearance on "The Kelly Clarkson Show" Tuesday,the actor explained how he ended up tattooing the wrong DNA ancestry result on his arm and why he decided to keep the ink.

The 44-year-old began by recalling how he'd given a lot of thought to getting a tattoo before taking the plunge.

"Right before I turned 40, I was like, 'I'm gonna do it. I've wanted them for so long,'" he said.

Penn showed off his ink to Clarkson, who thought it looked like "Mission Impossible" code. The idea for the tattoo came about after the actor appeared on the show "Finding Your Roots," where he learned about his ancestry.

"I thought, 'Alright, whatever they teach me, I'll get my first tattoo,'" he explained. "And I went on that show thinking, 'I want to find out that I'm a third Scottish and I can get a family crest.'"

The "You Can't Be Serious" author said he was hoping to discover something surprising and unique about his heritage but when he went in to hear his DNA results, he felt a bit let down.

"They go, 'You are 99.9% South Asian. How do you feel?'" he recalled. "I was like, 'Yeah, I know, it's so disappointing.'"

Related: The actor shared details about their relationship as well as their first date in his upcoming book "You Can’t Be Serious."

The show's crew showed Penn a map with the number R1a-M147, which is a maternal haplogroup he shares with millions of other people.

"It's basically your DNA ancestry and I was like, 'That's gonna be my first tattoo 'cause it's science,'" he told Clarkson.

Afterwards, Penn was inspired to dig deeper into his roots and bought his own DNA testing kit. The results from the second kit came back four months later but at that point, he'd already tattooed his arm, so he was disturbed to see that the kit's website told him he actually had a different maternal haplogroup of R1a-M417.

Penn's partner Josh was home at the time so he called him into the room and Josh had quite the reaction.

"I was like, 'Dude, come over here. What is the deal with this? Is this real? And the gleeful look on his face, like I have never seen him happier," he said. "Then I emailed them all and was like, 'What's the deal with this?'

"But now I kept it because it's a good story."

Clarkson then went on to describe the story of her first tattoo, which is a Japanese kanji character that she got done when she was 18. The singer said she was told it was supposed to mean "blessed," when she traveled to Japan a few years later, she made sure to ask some locals what it really meant.

"When I went to Japan, I was literally like, 'Please dear God, tell me this means blessed,'" she recalled. "They were like, 'It means blessed, but it also means like someone's surname' ... so I just have someone's family name on my body. It's fine; we make really good decisions at 18."

Advertisement