The need for DNAse I treatment depends on several factors, including:
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Samples with high DNA / RNA content (e.g., blood samples).
Low quality / FFPE samples.
Samples containing large quantities of short, extra-chromosomal DNA.
Samples that have undergone mechanical disruption (gDNA fragmentation can increase carry-over potential)
ATTENTION! DNase I should be removed before library preparation as it may affect the efficiency of the library generation.
NOTE: for more information on gDNA contamination and DNAse treatment, please, check also our RNA LEXICON Chapter #5.
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