Also do identical twins have the same DNA? i know they have the same finger prints ( well at birth they do, your finger print changes over time with small cuts and things.)
Daft as it sounds, you can have a scar across a print in any unusual shape you can think of and it wouldn't be evidential as far as fingerprints are concerned. Identification has to come from the ridge patterns within the prints themselves, and nowhere else.
Identical twins don't actually have identical prints, although they may be very similar, they do have differences due to all sorts of factors such as position in the womb, individual nutrition and other considerations. There has never been a case of two people having identical fingerprints in the whole history of fingerprinting, which is the reason that fingerprints are considered 100% conclusive evidence.
DNA profiling doesn't provide 100% conclusive evidence, which is why the evidence has to quote the odds that it could be someone else - usually many millions to one against.
Personally I think DNA profiling is the biggest advance in crime detection since fingerprinting. People are getting arrested today for shoplifting or dangerous driving and as a result getting convicted of horrendous rapes and murders from over 30 years ago - it's now a common occurrence for DNA to yield these sorts of results as the database has been running for over 20 years.
It wouldn't concern me in the least giving my DNA tomorrow if need be - I have nothing to hide or fear from it. Having said that, I value my freedom and personal liberty as much as the next guy, so I can appreciate the legitimate concerns some people have about the possible misuse of the database.