Obviously, DNA is strong evidence in the case of a rape. If a man's semen is found on a rape victim, it's very likely that he committed the rape. Other DNA evidence, from skin, hair, or blood can also shed light on a case. If DNA evidence supports other evidence, it should be taken account in the case of a rape.
How else are you gonna tell who the rapist was? You can;t say DNA isn't acceptable evidence because that would just be silly. If someone was raped they should be allowed to take a DNA sample from her pelvic region to determine who it was that raped her. It's the only solution to that problem really. I honestly can't think of any other way to resolve the case
DNA can be left behind by just touching the person. Or a pubic hair left in the toilet that they grabbed. They could just be trying to frame you and all they need it you to touch them and/or leave a few hairs around the bathroom or bedroom. No, It shouldn't be proof.