from: Amanda Knox's appeal rests on jailhouse letters, challenges to DNA evidence By ANDREA VOGT 12/06/2010
http://www.seattlepi.com/local/431257_knox06.html?source=mypi
The amount of Kercher's DNA found on the blade was such a trace amount it registered with a "too low" reading when analyzed.
A top geneticist at one of Europe's top forensic labs at the University of Salzburg confirmed in an interview with seattlepi.com that it is possible to amplify such a small amount of DNA, as Stefanoni did, until DNA can be identified.
But the expert added that
it would not be allowable unless the result could be reproduced, something police biologist Stefanoni said under cross-examination could not be done.
The Salzburg geneticist, who does forensic testing for police agencies in neighboring Austria, said that
in the university's certified lab (which has the highest certification available in Germany and Austria) different operators are required to handle suspect and victim DNA and that the various phases of DNA analysis happen in different labs along a "one-way street" to avoid the possibility of contamination.
Such protocols were not in place in Rome. In fact, Italy is noted for being behind on international forensic standards. For example, it is one of the last (and only) European countries to have not yet become part of the Prum convention, which sets basic guidelines for sharing of DNA data and other security information.