Jamie McCarthy/WireImage(LOS ANGELES) — That moment when you find out you and your friend are actually related: On Tuesday night’s episode of PBS' Finding Your Roots, Marisa Tomei discovered that she and Julianne Moore are cousins.

The show explained that the two actresses, who co-starred in Crazy, Stupid, Love in 2011, share “an identical stretch of DNA along their X chromosome.”

"Julianne? Julianne! Julie? You know we went to school together?" a surprised Tomei said, referencing their time at Boston University. "Jules! Oh, I can't wait to tell her."

She shared the news on Instagram as well, writing, "What an incredible gift to find out about my family’s roots with @HenryLouisGates! Eternally grateful for this generation and generations to come…. and the big surprise — discovering my friend is my REAL cousin! Hey cuz @juliannemoore!!!!”

Moore was equally thrilled, writing, "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 show did note, however, that while Tomei's ancestors are from Italy, Moore did not have any Italian ancestors that it knows of.

"A powerful demonstration of how DNA can bridge the divide that appears to exist between people of diverse origins,” the show’s voiceover said.

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