In its proper state, literally nothing.
>oh you evil nazi, you want children in the future to be born free of genetic health conditions like Tay-Sachs and Huntington's, how fucking dare you.
In its publicly perceived state, too many people have wrong and ill-formed views on the matter. For instance,
>>291949 this guy. While there are a rare few conditions that are genetically responsible for eyesight, they are few and far between. The vast, VAST majority of myopia today is caused by developmental factors such as how you spent your time as a child.
Intuit villages who had 95% good eyes in a single generation went to 50% myopia when western education was introduced, because the kids spent time indoors == not focusing far away outside and not getting enough sunlight. But you'll have retards (not suggesting the poster anymore) say "LOL PEOPLE WITH GLASSES SHOULDN'T BREED!"
And then there's stuff like this. "Exterminate the disabled!", overlooking the obvious fact that most "disabled" are people who were previously fine and then became not fine due to some injury.
>Autists
Look at the inclining autistic population. The gene pool isn't degrading (outside of ethnic factors) over 10 or so years, this is due to cases like pregnant women taking acetaminophen, and other variables I would lump together under the phrase "womb environment".
There are some genetic components, and some environmental components, explained elsewhere in post. However for some things like Trisomy 21 (downs), that's usually a spontaneous mutation. It's not like they're born from retarded parents (well, you know what I mean).
Sadly, this is the case. I am 100% pro eugenics, but I do not trust any modern day state to enforce it, given how they're trying they're best to be as dysgenic as possible.