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Principles of Forensic DNA for Officers of the Court

Exclusion or Non-match

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When comparing a known sample to an evidence sample, the donor of the known is excluded as a source of the evidence if the profiles are different. This can either be referred to as an exclusion or a non-match .

When an individual is excluded as the source of DNA, it does not necessarily mean the individual was not involved. For example, a true perpetrator who left no detectable biological material will be excluded as a source of DNA.

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