You need to hire a criminal defense attorney if you have been/will be charged with a felony offense. If the government has your DNA on a piece of evidence, that with other evidence about the crime, is something that must be dealt with. Other sources of DNA is something the defense can use if related to the "who" of the case, if identity is at issue.
I am trying to give you a general answer to your question. We do not have an attorney-client relationship by this response on the avvo website. I have not been retained to represent you. I am licensed to practice law in Kentucky and in federal court in this state and the Southern District of Indiana. You need to seek legal advice from an attorney licensed to practice in your area..
Rarely does a criminal prosecution rely on just one piece of evidence. This evidence plus other kinds of evidence would likely be used. That being said, having multiple sources for the DNA may allow you to claim some kind of third party defense. You should hire a defense attorney immediately to help you formulate a strategy.
You can call me at 612-223-7286 to talk more about your case.
It all really depends on the facts as to whether they can "pin the whole thing on one person." Remember, just because there is DNA does not necessarily mean the prosecution case prove a case beyond a reasonable doubt. There are many reasons why DNA could be in a certain place, and rarely would DNA alone be enough to convict. I do advice that you speak with a defense attorney about your case. Many of us offer free consultations where we can go over the facts of your case in confidence. Good luck.