I have to agree with you. (although using "synthetic" DNA would not be unusual, all DNA that results from PCR can be said to be synthesized)
If this is the case, they are misleading a lot of collectors and the Olympics commission which hired them.
From their website:
"This liquid includes a unique formula of DNA and optical labels with rare light-emitting chemicals. You can view the authenticating mark with a specially calibrated laser, which is set to the exact frequency used by PSA/DNA, and it will glow a bright green or red color"
They don't specifically say that the laser is detecting a unique sequence of DNA, only that it is detecting their special formula. Is this hype or an outright lie?
If this were the case, would they have to walk up to a vendor and apply the probe to the label? Not that it couldn't be done, but it seems impractical. (Please correct me if I'm wrong) Also, if they added the probe before printing it would ruin the specificity of the test, since it could be any DNA hybrid attached to the marker. Not that that kind of counterfeit DNA label would be practical for the counterfeiters, but in principle the specificity of the tag would still be gone. Their website seems to imply that they can detect the unique sequence of DNA with a specially calibrated laser without the prior application of a probe, which I find hard to explain.
In order for the sense strand to be able to hybridize for this, the DNA tag would be susceptible to degradation by washing the merchandise, right? (not that it would matter in this case-they just want to catch the vendors). Does a unique sequence of DNA emit a unique wavelength of light that can be detected? I don't think so, but I'm not sure.
The officials aren't concerned with busting the buyers, it's the vendors of the fakes that they want to shut down. If you shut down one vendor, you prevent a lot of revenue loss. It wouldn't be worth it to hunt down buyers, as one buyer is a very small portion of lost revenue. Also, a portable scanner is not impossible, just very clever. It sounds like the invisible ink wouldn't last through the washing machine in order for it to work with a portable scanner, but in this case they aren't concerned with catching the merchandise after it's been bought anyway.
I doubt they just confiscate a sample from every vendor and then expect to find them later...
My guess is that the scanner just detects that the ink is present, probably through something in the ink other than DNA, or by attaching another sort of molecule to the DNA itself that can be picked up by the scanner. Obviously, if this is all they check for then it would be easy to spoof, but I don't know of any way of making a portable scanner that could dectect a specific, unique sequence of DNA on the spot.
Actually, if they applied a piece of antisense DNA that had a marker attached to it that was chemically changed upon the antisense DNA binding to its matching DNA in the ink, then they could pick it up with a scanner (pick up the chemically changed marker that is). This would require putting some sort of liquid or substance on the merchandise in order for it to be checked though.
It is an interesting question.
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I have to agree with you. (although using "synthetic" DNA would not be unusual, all DNA that results from PCR can be said to be synthesized)
If this is the case, they are misleading a lot of collectors and the Olympics commission which hired them.
From their website:
"This liquid includes a unique formula of DNA and optical labels with rare light-emitting chemicals. You can view the authenticating mark with a specially calibrated laser, which is set to the exact frequency used by PSA/DNA, and it will glow a bright green or red color"
They don't specifically say that the laser is detecting a unique sequence of DNA, only that it is detecting their special formula. Is this hype or an outright lie?
If this were the case, would they have to walk up to a vendor and apply the probe to the label? Not that it couldn't be done, but it seems impractical. (Please correct me if I'm wrong) Also, if they added the probe before printing it would ruin the specificity of the test, since it could be any DNA hybrid attached to the marker. Not that that kind of counterfeit DNA label would be practical for the counterfeiters, but in principle the specificity of the tag would still be gone. Their website seems to imply that they can detect the unique sequence of DNA with a specially calibrated laser without the prior application of a probe, which I find hard to explain.
In order for the sense strand to be able to hybridize for this, the DNA tag would be susceptible to degradation by washing the merchandise, right? (not that it would matter in this case-they just want to catch the vendors). Does a unique sequence of DNA emit a unique wavelength of light that can be detected? I don't think so, but I'm not sure.
The officials aren't concerned with busting the buyers, it's the vendors of the fakes that they want to shut down. If you shut down one vendor, you prevent a lot of revenue loss. It wouldn't be worth it to hunt down buyers, as one buyer is a very small portion of lost revenue. Also, a portable scanner is not impossible, just very clever. It sounds like the invisible ink wouldn't last through the washing machine in order for it to work with a portable scanner, but in this case they aren't concerned with catching the merchandise after it's been bought anyway.
I doubt they just confiscate a sample from every vendor and then expect to find them later... My guess is that the scanner just detects that the ink is present, probably through something in the ink other than DNA, or by attaching another sort of molecule to the DNA itself that can be picked up by the scanner. Obviously, if this is all they check for then it would be easy to spoof, but I don't know of any way of making a portable scanner that could dectect a specific, unique sequence of DNA on the spot. Actually, if they applied a piece of antisense DNA that had a marker attached to it that was chemically changed upon the antisense DNA binding to its matching DNA in the ink, then they could pick it up with a scanner (pick up the chemically changed marker that is). This would require putting some sort of liquid or substance on the merchandise in order for it to be checked though. It is an interesting question.