When you mess up time travelling and become your own ancestor, there is a big problem:
At some point in time, a child will be born with exactly the same DNA as you.
Did any franchise address this problem? Because, as far as I understand, your descendants don't have your DNA.
So, as an example, you are your own grandfather.
- You travel back in time with your DNA.
- You "make" one parent of yourself with his or her own DNA.
- Your parent "make" you and normally your DNA would be different thanthe one of all recent ancestors