If you didn't call it a hobby, flykiller, they'd put you in one of those nice white tuxedos that ties in the back and fast courier you off to a nice complex with rubberized walls and no sharp corners.
To Andrew's point:
I'm 15/16ths Scottish, 1/16th Irish, and 100% Canadian. But at the same time, I wouldn't be surprised to find French, Russian, Welsh, and (hack) English in my genetic pedigree. And that's after a few generations (our Clan wasn't that old) here on Ye Olde Earth.
Throw in a couple more thousand and I've seen the thesis that we'll all be sort of mid-brown partly mullato-asiatic-dash of caucasian with mild epicanthic folds, brownish black hair, and brown eyes in a few hundred years... let alone a few thousand.
And we don't have piles of others to interbreed with (other Humanitis). So.... I come back to 'what is Solomani or Vilani'? If you mean someone who styles themselves of a particular origin (as I style myself as being mostly Scottish), then I guess that's okay - you'd be able to ask people what they consider themselves to be.
But that's opinion, fancy, and not genetics. Genetically, by 5600+ AD, we'll all be a big stew of mixed bag genes - it will probably be not just unlikely, but downright not feasible, to identify genetically pure solomani or vilani or any other sort of humaniti....
I guess my point is the discussion of race will be as pointless in the far future as it almost is now. I find it rather humorous that the statisticians have shown that even the average KKK member probably has some African genes in him by now (and likely vice versa). Now, cultural identification and perhaps even mild ethnocentrism may not be such a bad thing and I suspect it will persist into the far future, but the whole genetic purity thing is a crock.
So, any kind of data kept on racial breakdowns will really reflect 'cultural breakdowns' instead.