Surprise! Marisa Tomei & Julianne Moore Just Found Out They're Cousins on 'Finding Your Roots'

Marisa Tomei and Julianne Moore just got the surprise of a lifetime ... all thanks to DNA!

The "My Cousin Vinny" actress made an appearance on the PBS show "Finding Your Roots" and discovered she's cousins with the redheaded beauty! In the clip, it's revealed the duo share an exact strain of DNA along their x chromosomes and are "genetic cousins," meaning at some point, at some time in life they shared a relative.

But that didn't stop Moore from sharing her excitement all over social media!

"I KNEW WE WERE ALIKE! @marisatomei is my COUSIN!! OMG I’m so excited, thank you @henrylouisgates for letting us know we have identical segments of DNA - #FindingYourRoots #twinning," the actress wrote.

The "Crazy, Stupid, Love" co-stars go way back. The duo went to High School together and each got their start on the former daytime soap "As the World Turns.

Tomei's episode of "Finding Your Roots" airs this week.