Oh, honey, I'm half Norwegian and half northern German. If I were any whiter, I'd be translucent.
But yeah, the word mulatto should have made it clear that it was possible that Blair Underwood had European ancestry too, though it's quite possible that words like mulatto just got thrown on the record of anyone who looked as if they had a white ancestor too, as opposed to someone knowing for sure that they did. They also said that 25% European wasn't unusual for an African-American. In fact, it's about average, often due to the number of slave women who were sexually assaulted by their white masters and who had their children as a result. I thought Blair Underwood was just surprised that it was likely French/Swiss ancestry, because he'd always been so drawn to France.