Sea Squirt - Entire Body Regeneration

Inhabiting shallow coastal waters, sea squirts form colonies of genetically identical individuals. Ram Reshef and Yuval Rinkevich of the Israel Institute of Technology in Haifa and colleagues took fragments of blood vessels from the animals and watched under a microscope.

Out of 95 fragments they examined, 80 underwent whole body regeneration (WBR). Cells first grouped into hollow spheres, then cell layers in-folded and organs developed until after two weeks an adult sea squirt had grown, capable of sexual reproduction.

If a lesser being like a Sea Squirt can have that level of control over their body (or the other way around), I see no reason why Humans cannot select DNA repair in a beneficial manner...