Almost certainly impossible. It's not a matter of newer technology, it's just that DNA doesn't work that way. You'd have to have some kind of weapon targeted to a specific person's entire genome (based on a sample of it) to not end up with an insane amount of collateral damage.
Human DNA is almost identical in every human that lives, and genes are present in everyone that are not active. You'd try to target a given group of people with e.g. brown skin and short stature and you'd end up killing your neighbors plus some other random people half a world away.
