Whether literature is available on importance of various tissue components in relation to the PCR inhibition. There are many inhibitors of PCR like hemoglobin etc. Whether the site and tissue specific inhibitors list is available?
Inhibitors are very common with clinical samples. if yu have sufficient quantities of DNA, then try re-purifying an aliquot with a god quality stool/soil/plant DNA purification kit. These kits have particularly better ability to remove inhibitors.
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