I have been informed of a new DNA test to find a Cohen DNA strand in your DNA. Now I was wondering if someone were to take the test and were to find cohen strands of DNA in them would that be able to allow one to become a citizen in Israel since you have to prove that you are indeed Jewish?

The test you suggest doesn't make one Jewish either halachically or in the eyes of the State of Israel. Someone who is not Jewish but who would like to be should speak to an Orthodox rabbi about beginning the process of a halachic conversion.