Good New York Times article on the genetics.
We found out in the original written brief that the scientists tested more than 1000 samples from labs around the world. This is presumably an exhaustive sampling of all known samples of Ames strain anthrax.
Problem #1: They could necessarily only test samples of Ames strain anthrax that they already knew existed. What if there are samples of Ames strain anthrax that the scientists did not test because they did not know they existed? Aside from Saddams non-existent WMD anthrax research, I could easily imagine any number of other governments (including our own) with highly secretive bioweapons programs hiding this information from the FBIs anthrax investigators.
All the FBI can say is that the flask in Ivins’ possession is one possible source. They can’t prove that it is the only source.
Problem #2: To allay these concerns, the FBI can claim that it is likely that it is the source since, out of 1000 samples tested, all of the ones that matched could be traced to Ivins’ flask.
What?! More than one sample matched?! Yes a total of 8 samples matched. “B-but, b-but, they could all be traced to Ivins,” stutters the FBI. We already know that Ivins was not the only person with access to “his” flask. But now we learn that, in addition to the 100 other people who had access to Ivins’ flask, there are at least 7 other people (and probably many, many more) who had access to anthrax that is biologically identical to the mailed anthrax. These 7 other samples were not located at AMRIID.
So, although we were initially told by the FBI-parroting media that sophisticated scientific techniques could uniquely identify Ivins’ flask as the smoking gun, we learn that even this flimsy piece of evidence isn’t true: there are 8 known smoking guns and a theoretically infinite number of unknown smoking guns.
Kathryn Muratore is an Assistant Professor of Chemistry at American University. She holds a Ph.D. in Molecular and Cell Biology from UC Berkeley.
source: http://www.lewrockwell.com/orig7/muratore9.html