What would happen if one (and only one) human could magically modify their genes, while everybody else and the laws of physics and biology remained the same? That effect wouldn't appear immediately. The change rate would be slow, taking weeks and months to see the difference.
I can think of some scenarios:
- They can make their brain work more efficiently, but the consequence is that they need to absorb more energy (and get more tired, but I don't know if this is biologically necessary).
- With a salient brain, that one can process on more information, therefore they can rule the world. I think this one can only be stopped if they are required to sleep longer, so that the world changes fast enough while they are sleeping.
- In order to be able to work without sleep, they decide to upgrade their meat brain to a silicon brain. Ultimately, they will transform to a self-coded super computer.
- But a computer is only free in the World Wide Web. In a physical world, it needs to depend on the electricity supply. So they (or it now?) face two choices: self supply or seeking help. Which one should they choose?
- And because they have watched the I, robot movie, and because they are not a production of anyone, they decide to not kill a vast majority of humanity at the same time.
How else can the story go? Which idea above can go in a different way?