There is no law explicitly against human genetic engineering in the USA, but there are in most countries.

This has been going on for years in animals, where unintended consequences are very obvious because the genome is a massive complexity of higher order interactions. The idea of one genetic change having one predicted effect is just ignorant.

I never thought eugenics would come back after the horrors of Josef Mengele. If he had gene editing technology, his efforts could have been even worse for humanity.