I’d say racism as we know it today owes a lot to Genesis and the story that Noah’s sons were each responsible for a race. Even though many who believe using a racial taxonomy based on pseudo-genetics is “scientific” (let’s say “eugenic”), I’d say if they’re Eurasian it’s likely this Biblical underlayer is informing their thinking by osmosis.
See if they think the Middle East is “where it all began” in terms of civilization and so on. That’s evidence of “Sunday School programming” of some kind.
That being said, I accept the need to taxonomize and distinguish. Whereas I wouldn’t think “Africans are black” (I know many white Africans) I would agree that many are, and that “blacks” are more prevalent per capita in Nigeria than say “yellows” or “reds” (as if skin hue were a “marker” relating to one of Noah’s sons).
I’m not above using the prevalent “black, white, red, yellow, brown” parody racism I think of as “corporate brochure” racism, i.e. for dummies (“corporate” = “needs it dumbed down” in my book), when that’s convenient. I’m OK with using the vernacular, just not with developing fervent beliefs around it (I’m too snobby for that).
But then ethnicity is centrally epigenetic, not genetic at its core. For example, even though I have white (pinkish) skin, I feel little ethnic affiliation with many pinks (e.g. the ones who talk about “superpowers” outside of comic books, or of the US presidency as the “most powerful office on earth” — that’s the dork race that believes that kinda nonsense), and that’s also true of many whites I’ve met: they’re not into their own “whiteness” as significant except maybe they have a high tolerance for mayonnaise and lawn dwarves (i.e. they’re effected by all the stereotypes).
In summary, it’s Genesis (the book) more than genetics (DNA studies) that underpins our conception of “the five races of man” (or is it seven — however many sons Noah had, I forget).