Objectives: To assess whether different genomic cell-free DNAs are equally abundant in the plasma of individual donors, and any relationship between DNA methylation and representation in plasma.
Design and methods: The concentrations of DNA in plasma were determined by real-time PCR.
Results: Different DNA sequences were not equally represented. The relative abundances were similar in different donors.
Conclusions: Different DNA sequences are not equally abundant in plasma, with no relationship between DNA methylation and abundance.