Circulating cell-free DNA (ccfDNA) is a promising diagnostic tool and its size fractionation is of interest. However, kits for isolation of ccfDNA available on the market are designed for small volumes hence processing large sample volumes is laborious. We have tested a new method that enables enrichment of ccfDNA from large volumes of plasma and subsequently allows size-fractionation of isolated ccfDNA into two fractions with individually established cut-off levels of ccfDNA length. This method allows isolation of low-abundant DNA as well as separation of long and short DNA molecules. This procedure may be important e.g., in prenatal diagnostics and cancer research that have been already confirmed by our primary experiments. Here, we report the results of selective separation of 200- and 500-bp long synthetic DNA fragments spiked in plasma samples. Furthermore, we size-fractionated ccfDNA from the plasma of pregnant women and verified the prevalence of fetal ccfDNA in all fractions.
Cell-free DNA DNA size-fractionation Prenatal diagnostics Cancer research
This is a preview of subscription content, log in to check access.
Conflict of Interests
No potential conflicts of interest were disclosed.
Ashoor G, Syngelaki A, Poon LC et al (2013) Fetal fraction in maternal plasma cell- free DNA at 11–13 weeks’ gestation: relation to maternal and fetal characteristics. Ultrasound Obstet Gynecol 41:26–32. doi:10.1002/uog.12331CrossRefPubMedGoogle Scholar
Chan KC, Zhang J, Hui AB et al (2004) Size distributions of maternal and fetal DNA in maternal plasma. Clin Chem 50(1):88–92CrossRefPubMedGoogle Scholar
Chiu RW, Lo YM (2013) Clinical applications of maternal plasma fetal DNA analysis: translating the fruits of 15 years of research. Clin Chem Lab Med 51(1):197–204PubMedGoogle Scholar
Schwarzenbach H, Hoon DS, Pantel K (2011) Cell-free nucleic acids as biomarkers in cancer patients. Nat Rev Cancer 11(6):426–437CrossRefPubMedGoogle Scholar
Schwarzenbach H, Eichelser C, Kropidlowski J et al (2012) Loss of heterozygosity at tumor suppressor genes detectable on fractionated circulating cell-free tumor DNA as indicator of breast cancer progression. Clin Cancer Res 18(20):5719–5730CrossRefPubMedGoogle Scholar