Remember a couple of months ago, when I discussed testimony at the Autism Omnibus trial that showed how Andrew Wakefield had failed to do the controls when running PCR that would have revealed that the results that he interpreted as the presence of the measles virus from a vaccine strain in the guts of autistic children was nothing more than a bunch of false positives due to widespread contamination of the laboratory with plasmid containing measles sequences?
It turns out that it's not just autism pseudoscientists who forget to do the right controls when running PCR. Mike the Mad Biologist describes an example of a very similar sloppiness of experimental technique in the microbiology world that also lead to what is almost certainly a false positive result.
I just can't understand how such obvious, first year graduate student mistakes manage to get published in the peer-reviewed literature. It doesn't happen that often, but it does happen at a rate that is high enough to be distressing. In the case of Andrew Wakefield, the results of his sloppy science were catastrophic, namely an antivaccination scare about the MMR that nine years later still hasn't fully run its course.
A negative control is a must in PCR, I routinely run primers on the male specific SRY gene on intersex horses and last year every thing started turning up positive including my negative controls, the graduate student on the next bench had been cloning the SRY gene into a plasmid and had contaminated all my reagents. Without negative controls I would have been none the wiser.
Catastrophic seems almost an understatement-----it's the sloppy science that launched a thousand quack autism treatments, and more false hope than the Trojan Horse.
It also needs to be pointed out that there exists the possibility that the controls were run... and decidedly ignored. Yep, it's either incompetence, dishonesty, or a combination of the two. A healthy income from the results you like probably makes the decision to toss the "bad" results "easier".
/Quotation marks by Bennett Brauer