The Importance of Careful Blood Processing in Isolation of Cell‐Free DNA

Abstract
Abstract:  In healthy individuals, the source of cell‐free plasma DNA is predominantly apoptotic, whereas, increased plasma DNA integrity is seen in cancer patients. Therefore, it is important to carefully isolate absolutely “cell‐free” plasma DNA. Plasma DNA from 30 healthy females was analyzed using 4 PCR amplicons of increasing size, comparing standard blood processing with additional centrifugation steps prior to DNA extraction. Cellular DNA contamination, indicated by positive amplicons >300 bp was eliminated only after the extra centrifugation step. This highlights the importance of careful processing in preparation of cell‐free plasma DNA as a tool for cancer detection and we recommend the use of a microcentrifuge spin, prior to DNA extraction.