Now that we have easy and open access to DNA testing, family mysteries are often mysteries no more.

But for people across the globe, family trees remain an often murky subject.

It’s part of why celebrity genealogy shows are so gripping — don’t we all wish we could have a team of researchers and DNA experts at our disposal?

Since 2012, the PBS series “Finding Your Roots,” hosted by Henry Louis Gates Jr., has illuminated the family trees of public figures including actors, artists, musicians, journalists, filmmakers and activists.

Gates, the Alphonse Fletcher university professor at Harvard University, is the director of the Hutchins Center for African and African American Research at Harvard. With the scholar at the helm, the show has shed light on the family histories of New Jersey celebrities including Queen Latifah, Nathan Lane and Paul Rudd.

Some details are small revelations, like the fact that Rudd’s parents are second cousins. Others come as a complete surprise, like when Latifah gazed upon the 1792 document that freed her first ancestor from slavery (see video below).

“Finding Your Roots” is also known for drawing links between guests. Sure, he played the senator and former presidential candidate on “Saturday Night Live,” but Larry David and Bernie Sanders are also distant relations, something the show discovered.

Many episodes leave A-listers in tears.

Genetic genealogist CeCe Moore, an expert…