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Principles of Forensic DNA for Officers of the Court

DNA Separation

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For genotyping to occur, the extracted and now amplified DNA must be separated so that alleles can be differentiated from each other. There are two primary methods used for DNA separation: slab gel electrophoresis and capillary electrophoresis (CE). These techniques produce identical results in a variety of visual formats.

The electrophoresis process uses an electric field to separate negatively charged DNA based upon the size of the amplified fragments.

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National Institute of Justice (NIJ) (see reuse policy).

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