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Technical Suggestion
•
While line 8 is true it is not part of the specificity
testing which should be done early on in testing.
This soil should be tested with other gold standard
methods to insure the target sequence is absent.
Then and only then can it be tested with the assay
being developed. If the assay is positive in a soil
declared negative the assay fails because it is
giving a false positive response. Testing with the
target spiked at 2X plus a native DNA control
without soil DNA will identify the presence of
inhibitors.
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Technical Suggestion
•
DNA containing soil inhibitors can be tested at 1X
and dilutions up to 50X to overcome any inhibitor
response. The assay could be very specific (and
sensitive) allowing field samples to be diluted
prior to testing to overcome those inhibitory
substances. Removal of inhibitors is different than
testing for specificity and is a function of the DNA
extraction method.
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