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Cotton Swabs are the Prime Suspect In 8-Year Phantom Chase
matt4077 writes "For eight years, several hundred police officers across multiple European countries have been chasing a phantom woman whose DNA had been found in almost 20 crimes (including two murders) across central Europe. It now turns out that contaminated cotton swabs might be responsible for this highly unusual investigation. After being puzzled by the apparent randomness of the crimes, investigators noticed that all cotton swabs had been sourced from the same company. They also noted that the DNA was never found in crimes in Bavaria, a German state located at the center of the crimes' locations. It turns out that Bavaria buys its swabs from a different supplier."
http://news.bbc.co.uk/2/hi/europe/7341360.stm Until that server comes back up, here is an article from a year ago about the case. Makes for hilarious reading now!
Here's the wikipedia page about the case. I think the original source of the news is in German though.
09F91102 no, 455FE104 nope, F190A1E8 uh-uh, 7A5F8A09 that's not it, C87294CE no. Ah! 452F6E403CDF10714E41DFAA257D313F.
I work with a lot of labs and the errors are always caused by the lab technician. Controls and variances are standard procedure to identify Wal-Mart grade results. From my experience, the less you pay a lab tech, the more mistakes they make, but there are exceptions, like trying to find an honest cop. I'm sure there's one or two, maybe.
Also, they're worried about people going through police training, getting it for cheap, then quitting for a better-paying job.
If you have a process to keep things sterile, then you would not just have everyone handling the things wear gloves, but also surgical masks. It doesn't make much sense to have one without the other.
Accourding to the german news site spiegel, they DID test raw material, but didn't find the offending DNA in the samples. If only a small fraction of the swabs are contamined, it can take a long time until you find one.
OJ didn't do it!
For the benefit of the idiot who moderated the parent post offtopic: OJ got off primarily because forensic evidence was grossly mishandled, leading to its inadmissibility in court. (IANAL, but I am qualified in forensics.) The comment might be boring or unfunny, but not wholly offtopic.
Erm. I'm going to take a shot at this. The word you were looking for was affected, not effected. As indeed the linked definition should have made clear you. I can't be bothered to post links to the definitions of those words, but you know where to look..
http://www.spiegel.de/international/germany/0,1518,615608,00.html
If you can't be good, be good at it!
Oh, it can still be perfectly sterile.
Sterilizing something, that is killing off everything on and in it that lives, is pretty easy.
But completely removing DNA and other particles isn't. There could still be DNA particles from the person who picked the cotton in the cotton swabs.
When you have a little cell in the swab, there is no easy way to figure out if that is a human cell or a cotton cell, and remove all human cells.
And there *definitely* still is cotton DNA in the cotton swab.
Actualy there is a process when making the sex-cells that mix the genes from the two chromosomes in the chromosome pair. So none of the chromosones in the semen is actually a direct copy of the ones in the rest of your body.
That's quite possible, contamination of the gate oxide with various ions is a big issue with MOSFETs. Sodium ions in particular tend to be rather common in the air, so they caused a lot of problems. If it's particularly contaminated then you can't make enhancement-mode ("normally-off") devices, because the charges stored in the oxide lowers the threshold voltage below 0V. So to turn it off, you need a negative voltage, which is much less convenient than just having ground and a positive voltage.
In a small cleanroom at my university, just a simple one for the device processing classes, the lab manager said that in the past some students had opened a window because it was very hot in the room with the oxidation and doping ovens. Now it just so happens that the Pacific Ocean is about 200 yards from this window, so we have *lots* of sodium in the air. It allegedly took months before the sodium fully dissipated, so the mosfets that students made were poor-quality until the sodium levels dropped.