"You're going a bit too far when you say race is not a consistent genetic attribute."
Actually, race itself is NOT a single genetic attribute, but is made up of many individual genetic attributes. And very few if any of these attributes are linked. As such, breeding between races (forced or cooperative) can mix and match these attributes in such a way that you can end up with Negroes who have Roman noses and straight hair, as well as Caucasians who have Negroid facial features and extremely curly hair. It must also be remembered that many of these racial features are not caused by a single gene, but are the result of metabolic or developmental pathways that are controlled by many genes, thus making "mix and match" by breeding far more likely.
The only factors that have kept racial features consistent have been geographical (now overcome by technology) and social; there are virtually no genetic factors that insure genetic consistency in races.
Kevin L. O'Brien
"Good God, consider yourselves fortunate that you have John Adams to abuse, for no sane man would tolerate it!" William Daniels, _1776_