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Principles of Forensic DNA for Officers of the Court


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illustration of DNA Double Helix broken into pieces
National Institute of Justice (NIJ) (see reuse policy).

Degradation is the breaking down of DNA into smaller fragments by chemical or physical processes. Degradation of DNA may limit its use as evidence.

When DNA degrades, the DNA strand starts to break apart and these breaks can be at the sites where the DNA profiles are obtained. Because of the damage of the strand, none or only some of the 20 loci as required by the National DNA Database (CODIS) may be obtained.  Access information about CODIS.

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