But humans aren't divided into three races at all, genetically speaking. Just saying, race is a myth, scientifically there are no races, there's just humans.
This can't be serious.
Just because 4chan is closing down doesn't mean you should take its rhetoric and memes here.
Races, economics, gender roles, and so on: it seems that every week or so someone starts a thread about how some of the game's aspects don't match their worldview and then people go on about whether this worldview is universal or natural or whatever and it goes on for pages because someone read on wikipedia that some tribe somewhere doesn't do things as expected from that worldview so clearly it means that worldview is wrong except that someone pulled a psych study from some journal that says the contrary and so on...
It's just a game, people. Yeah I get you want it to be realistic (i.e. to match best what you think is real life) but if a suggestion is likely to spark controversies about silly topics like the existence and scientific validity of human races or whether gender roles or economic systems are "hardwired into brains" (as tech-savvy people who know nothing about how brains work often like to say) and all these lovely discussions that a certain demographic of the internet who may overlap with the aforementioned, soon-to-close-down place delights to take part in, you can be sure as hell that Toady isn't going to touch it with a ten foot pole. So yeah, expecting him to implement 19th century style human classification in his fantasy game is nothing short of preposterous, and on par with the implementation of hardcoded sexism, or homophobia, or rape, or excrement (these are legitimate suggestion threads I read lately, which makes me wonder what these people are actually believing about Toady).
Once it's established that none of this is going to happen, any further discussion about the aforementioned topics (whether the points being made are valid or not; that's beside the point) is basically just debating for the sake of debating, and has little to do on a game suggestion forum.
As for genetics themselves, they're already in, sort of. Given how the effects are mostly cosmetic, I think a detailed system would be probably superfluous, except if you wanted freaky things like X-men style mutations to happen, but what would be the point when you already have perfectly serviceable magic to implement and take care of the freaky stuff?