Among all the moral problems, there is also a technical problem: we don’t know that much about the relationship between IQ and genetics. Not even close to enough. We can’t even reliably predict something as straightforward as eye color outside of very simple situations and that is far clearer than the genetics of building and operating brains.

Not only is the genetics that underlie human intelligence complicated, so too is understanding intelligence itself. It’s not even clear that human intelligence can sensibly be reduced to a single number, or even a set of numbers, let alone ones that can be used to ordinaly rank people.

The situation isn’t much, if at all, better for any of the other traits they list. There may be some useful screens for specific mutautions that result in particular diseases that are well understood, but when it comes to the full understanding and subtlety of more complex traits, human genomics just isn’t there yet.