Geneticists do, basically.

Haplogroups.

That's a much better inclination.

Cow Milk? Yes/No?

That'd be my first thought, in your line of thinking.

... but you can tie that back to... bloodlines, lineage, peoplegroups, haplogroups, whatever word you want to use.

Most east asians just literally do not have the genetic lineage to support regular consumption of dairy products, the way most europeans do.

Because... we (hi, I'm white) come from a long line of cow milk drinkers, east asians do not.

Its funny reading a bunch of article headlines like "why are so many east asians lactose intolerant?"

No. Fucking, no.

We're the weird ones.

We are the ones who essentially decided to become mutants, due to our dietary choices.

What other animal regularly drinks the milk of another species of animal?

Here's another weird one:

Redheads.

(At least broadly 'white european' redheads)

They ... experience pain differently.

While they have an overall higher pain tolerance, they are also more sensitive to certain kinds of pain, and they need a somewhat higher dosage of something like novacaine to experience the same levels of pain reduction as a non redhead.

So basically, if you have a redheaded east asian child, don't give them a high dairy diet.

You'll hurt them, literally.

(this is mostly a joke, i dont really know if ... that would be the case. it seems to follow, as ... the two things i described, they seem to operate independently on different genes/gene clusters, but genetics is all about finding out how things you would not expect to be connected, actually are)