ALBUQUERQUE, N.M. >> Harvard scholar Henry Louis Gates, Jr., hopes this season of his popular PBS series “Finding Your Roots” helps a divided U.S. see how all Americans have unique family links and how those family histories tell the story of the country.

Now in its fifth season, the series takes advantage of new advancements in genealogy and genetics to look into the history of American celebrities. In upcoming episodes Gates and his team investigate the pasts of diverse subjects like former U.S. House Speaker Paul Ryan, Rep. Tulsi Gabbard of Hawaii and “Game of Thrones” author George R. R. Martin.

The show on Ryan and Gabbard airs on most PBS stations on Tuesday (8 p.m. in Hawaii). Last month, Gabbard was among the first prominent Democrats to announce her intention to run for president in the 2020 election.

“I get lots of letters and lots of comments and they tell me they love the way we can use DNA in combination with the paper trail to solve family mysteries,” said Gates, director of the Hutchins Center for African & African American Research at Harvard University. “We couldn’t do this 10 years ago.”

Gates said investigators were able to locate some of Ryan’s ancestors in Germany back to 1531. They also found that the former Republican leader is a descendant of Ashkenazi Jews, based on his DNA. “He almost fell over,” Gates said. “As the brothers on the streets say: DNA don’t lie.”

Gates said he’s especially proud that a previous show this season was able to help former “Saturday Night Live” star Andy Samberg find his biological grandmother and grandfather. His mother, who was adopted, never knew her biological mom. She turned out to be from a German-Jewish family that emigrated to Berkeley, California, during World War II.

But the show’s detectives not only located photos of the missing couple but also found half-siblings and cousins. The series filmed an emotional reunion with Samberg, his mother and their family.