Well, I don't mean literally killing the Kryptonian race.
Jor-El, managed to steal the Codex and bond its genetic information with the individual cells of his newborn son Kal-El.
And from the movie we are told that there is 1 billion pieces of DNA stored in the codex. Then in the movie we are shown the bonding process that Jor-El did to Kal-El. We are shown what seems to be DNA code bonded to blood cells.
Now we know that Superman can bleed from when he was struck in the scout ship and when he was on board General Zod's ship.
So in effect, when Superman bleeds he is losing not only blood, but valuable Kryptonian DNA data. And there is approximately 5,000,000,000 blood cells in 1 milliliter of blood. Of coarse we are not told what the distribution is, but you could definitely say a lot of information would be lost when there is blood lose trauma.
Is there any info on this, canonical or not?