In genetics it is well known that a specific gene is able to affect multiple unrelated phenotypes (the term for this is “pleiotropy”). Intelligence is not close to being understood, and there is no agreement about how to quantify it. But we do know that the brain is very complex, and that the genes that control how the brain develops and how the brain functions can express proteins that have more than one function or, in the case of regulatory genes, serve different regulatory functions in different tissues and/or life stages. Because of this, mutations that affect intelligence are very likely to show significant pleiotropy.

So, I do not think that it will be possible to introduce mutations that will only improve intelligence. An “enhancement” is likely to be more of a “trade-off”. I don’t think that it would be ethical to introduce any type of mutation if this is the case.

But I don’t completely rule it out. If future research does show that there are specific mutations that can considerably enhance some aspect of intelligence without having an impact on other traits, and if technology progresses to the point in which we can genetically manipulate a zygote with very high precision, then yes. I think that the descendants of the descendants of our descendants should explore that option. It is way too soon now.