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Security / Re: Fingerprints !
« on: January 07, 2013, 06:35 am »
If you are arrested for anything, they take your fingerprints. Even if your case is dropped later, your fingerprints are in a database somewhere. So far, they've mostly been taking DNA samples from convicted felons, as noted earlier, but I believe that is going to change. In ten years, they will probably be taking DNA samples from everyone who gets arrested.
DNA is much more accurate than fingerprints. With fingerprints, it's not like CSI where you see a million images flash across the screen and then they get 100% match. They find a collection of similar fingerprints and a human decides whether they have a match. With DNA, they use a collection of 13 short tandem repeats. Every person has a unique combination of those STRs, except identical twins. Identifying a unique individual is more straight forward. For now, fingerprinting is cheaper, but the cost of genotyping is falling fast and will eventually replace fingerprinting.
The other advantage of DNA is that you shed it from every surface of your body, so it doesn't rely on just the tips of your fingers coming into contact with a crime scene.
DNA is much more accurate than fingerprints. With fingerprints, it's not like CSI where you see a million images flash across the screen and then they get 100% match. They find a collection of similar fingerprints and a human decides whether they have a match. With DNA, they use a collection of 13 short tandem repeats. Every person has a unique combination of those STRs, except identical twins. Identifying a unique individual is more straight forward. For now, fingerprinting is cheaper, but the cost of genotyping is falling fast and will eventually replace fingerprinting.
The other advantage of DNA is that you shed it from every surface of your body, so it doesn't rely on just the tips of your fingers coming into contact with a crime scene.