The DNA found at each crime scene actually came from a female worker in the factory that manufactured the cotton swabs used to collect evidence.

事实上，在犯罪现场发现的DNA都来自生产采证棉签的工厂的一名女工。

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Guandique repeatedly denied involvement in her murder, and prosecutors acknowledged a lack of DNA evidence linking Guandique to the crime and a lack of witnesses.

CNN: New hearings in Chandra Levy case add to mystery

On the other hand they also find themselves at pains to explain that one of television's fictional devices an unequivocal match between a trace of a substance found at a crime scene and an exemplar stored in a database, whether it be fingerprints, DNA or some other kind of evidence is indeed generally just fiction.

ECONOMIST: Forensic science

If the justices rule for King, more than 1 million DNA profiles that have been stored in a federal database for matching with future crime scene evidence may have to be purged and others will never be collected, leading some repeat offenders to go free, advocates say.

NPR: Court Takes Up Question Of Arrestee DNA Sampling