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DNA Extraction From Fingerprints
Myriad writes "A Canadian scientist has developed a new way of gathering DNA evidence for analysis using fingerprints. The new test can extract DNA in 15 minutes - even from a print stored for many years and in varying conditions. The patented extraction technique consistently produces ~10 nanograms of DNA. Analysis generally requires 5-10 nanograms, although it is possible with as little as 0.1 nanogram."
You always have the problem of getting it admitted in a US court. Expect big battles over this. For example, if the judge isn't the most tech-savvy judge around, someone could bullshit him/her into believing that the DNA samples are unreliable. Also, you have the BigBrother concern. However, fingerprints are already considered uniquely identifying. The only added problem w/ getting DNA from fingerprints is technology that is still years away, if it even comes to the market -- predicting people's characteristics/future death from DNA. However, the only reason to get the DNA from the fingerprint and not from the sweat that the person left, or the hairs that the person left, etc., is because of the storage factor. So, while people worry about their DNA being extracted from a fingerprint, they should be more worried about all the hair follicles and skin cells they are leaving behind that also give away their DNA.
Yeah, we all know what the source of the DNA is on Slashdot users' fingerprints...
"Derp de derp."
This technology can be and is used for more than just fingerprints. The article says that this technology isn't new - the Canadian just came up with a better way of doing it. As far as contamination, other cellular residue is easily spun out, you buy kits for that, that part is fast and cheap. The main thing I would be worried about is the purity of the sample as far as number of sources of DNA. Lots of people touch alot of the same things.
partially correct. sweat molecules do not contain DNA...DNA is a seperate molecule. what they're getting the DNA from is the nucleus of any skin cells left behind
current dna testing relies on "marker" regions which are supposed to be present in a unique combination for each individual. however, because this is not a whole sequence comparison, there is a small chance of a false positive error but smaller than that of false positives using fingerprints. Indeed the marker regions were selected because they were (relatively) fast to test and did not give away information about the suspect (eg. race or eye colour, although one of the markers was later found to be linked to diabetes).
i think that this technology will eventually find its way into our courtrooms, and this is good. what would be bad is if we thought that any technology was so perfect that we didn't need a trial and we could go out hunting bad guys on their dna evidence alone.
there is no substitute for a public trial where all the evidence gets laid out on the table and a reasonable judge ensures that all parties are treated fairly. if that doesn't happen for the least of our citizens, then it's time to go find another country to live and work in. I've moved countries twice, and i'm always watching with my overnight bag under my desk.
beyond crime there are benign uses for dna identification. the Army DNA registry would also serve as a way to identify the dead, who have been blown up beyond recognition. this gives valuable closure for families and loved ones.
paternity testing now requires that you have a live man to take a sample from. with this new tech you could get the dna fingerprint from the inside of a locket or something.
the way i see it, leaving dna is like a form of subconscious, automatic grafitti. we are always tagging our environment with the words "i wuz here."
it's just that these days, there might be people around who care to read it.
DNA extracted from the region of a fingerprint does not prove that the DNA came from the fingerprint.
Residual DNA coats every surface and depending on the environmental conditions, whether it is inside or outside exposed to the sun, many other sequences will be present.
Current sampling and extraction techniques can not avoid this contamination and if your favorite hangout turns out to be a murder scene, well you are in trouble. While control samples taken at the scene in areas where 'no fingerprints' occur can be taken to test background DNA, it certainly is not foolproof.
Additionally, races and skin types slough skin at different rates and have significant oil-content differences, so there will also likely be a discrepancy in who gets caught. tough luck.