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Principles of Forensic DNA for Officers of the Court

DNA Typing - Short Tandem Repeat

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The current state-of-the-art DNA testing utilizes technology which combines the best features of RFLP and PCR.

This method examines a subclass of VNTR regions of the DNA molecule that tend to repeat themselves in short, adjacent, or tandem, segments. STR technology can use partially degraded, small quantity DNA and has a very high degree of discrimination.

'Multiplex' STRs are groups of genetically independent STR markers that can be examined at the same time. These multiplexes have proven to be very successful and provide the basis for the local, state and national DNA database entries.

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