According to Memory Alpha, Augments, as compared to normal humans:
* were five times stronger
* were more agile
* were twice as intelligent
* had greater resistant to sickness
* had greater sensoral acuity
* had heart muscles with twice the strength
* had lung efficiency that was 50% better
* had twice the lifespan
All these could be accomplished through advanced genetics. We are already changing the nature of animals and plants through genetics. Given time, we might be able to do the same with humans.
Khan has suddenly, in this new film, become Jesus. He has this remarkable dunamis that, if tapped, could revive the dead. We have moved past genetic re-sequencing and have moved into the supernatural.
Welcome to Star Trek.
Not unless your TREK revolves around who has the biggest stem-cells.