I think we can find people descended from the Mayans. Now finding people actually descended from the Egyptians of Antiquity, I don't recall how tricky that is, but I imagine it's not a huge obstacle, considering that apparently despite the best efforts of the Angles and Saxons and Jutes and Danes and Swedes and Norwegians and Scottia, most ethnic-English are still predominantly Brythonic Celt, IIRC.
So I'm pretty sure that we could actually check to a certain extent. Indeed, if I could find a source to back it up, I'd actually go so far as to swear that they'd already checked.
As it is... I sincerely doubt it.