I'd bet - - -
DNA has found it's way to Mars.
Whether it found the conditions under which it could replicate, I don't know.
While I have almost boundless faith in the ability of DNA to take advantage of many, many sources of energy found on more or less temperate planets, there are limits to it's physical integrity.
And whether enough DNA found it's way to Mars to ever be located is interesting.
I kinda like Phil's argument. I know one of the reasons for going to the Moon was to find the secret of life. Well, that's a rock. No life, no real secrets.
So, I'd bet there's DNA on Mars, or old DNA, and not necessarily DNA of Mars origin. But it probably hasn't replicated.
Arf