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DNA Amplification for Forensic Analysts

Calculations & Dilutions

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The quantity of DNA added to an amplification reaction, along with the overall volume of the amplification itself, impacts the quality of the results. The multiplex kit manufacturers vary on the suggested input template DNA as well as the suggested reaction volume size.  For example, the Profiler Plus User's Manual recommends 1.0-2.5ng of DNA in a 50µl reaction.13 while the PowerPlex® 16 kit recommends 0.5-1.0ng of DNA in a 25µl reaction.14

Read more about DNA amplification this course.

Some laboratories have successfully validated reduced reaction volumes in part to limit the consumption of DNA evidence and reduce analysis costs.15   These validation studies have included assessment of preferential amplification, heterozygous peak height ratio, and an overall comparison between the reduced reactions to that specified by the manufacturer.  As with the implementation of any new methods, laboratories must conduct appropriate validation studies.

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