It cannot, as it would interfere morally, physically, and mentally with the wellbeing of the growing fetus. Ethically speaking, changing the dynamic of something that has existed forever is wrong. A process such as natural selection, discovered by Charles Darwin, allows for nature to take its course in the biological making of humans. Nature is necessary in development because the body naturally adjusts to its surroundings, and then thrives based on that. Without this, or with science’s take over of this process, more issues in the world could arise such as overpopulation, hunger, and a lack of resources. With that, comes the value of nature vs. nurture and how both are needed to form a healthy human being. Genetic modification would take this away, if approved.
Alongside the argument for ethics is the fact that the procedures for genetic modification are in developmental phases and are unpredictably detrimental to the growing human. It is unknown how a surgery or cell transfer method would react for the fetus being treated or the mother. With so many unknown factors and the difficulty of testing trials on humans, the process can never be fully proven to be safe and standard. Embryos are developing humans and should be treated as so, and therefore not used as test subjects in the