You could just have the government mandate a test, and any embryo that has markers (genetic or otherwise) of a chronic debilitating condition is not allowed to be brought to term. If parents do choose this, the kid will fall outside of the healthcare system for its condition and parents will have to foot the entire ongoing bill.

Eugenics does not automatically mean we all customize our embryos to be 2m tall geniuses with patterned body hair.

More of an aside, but I’ve always wondered where humans would end up if we did do unbridled genetic engineering. Is 2m the ideal height? 1.80m? 2.40m? What would we discover is the optimal IQ? Etc.