Integration of Cell-Free DNA End Motifs and Fragment Lengths Can Identify Active Genes in Liquid Biopsies

Christoffer Trier Maansson, Louise Skov Thomsen, Peter Meldgaard, Anders Lade Nielsen, Boe Sandahl Sorensen*

*Corresponding author for this work

Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaperJournal articleResearchpeer-review


Multiple studies have shown that cell-free DNA (cfDNA) from cancer patients differ in both fragment length and fragment end motif (FEM) from healthy individuals, yet there is a lack of understanding of how the two factors combined are associated with cancer and gene transcription. In this study, we conducted cfDNA fragmentomics evaluations using plasma from lung cancer patients ( n = 12) and healthy individuals ( n = 7). A personal gene expression profile was established from plasma using H3K36me3 cell-free chromatin immunoprecipitation sequencing (cfChIP-seq). The genes with the highest expression displayed an enrichment of short cfDNA fragments (median = 19.99%, IQR: 16.94-27.13%, p < 0.0001) compared to the genes with low expression. Furthermore, distinct GC-rich FEMs were enriched after cfChIP. Combining the frequency of short cfDNA fragments with the presence of distinct FEMs resulted in an even further enrichment of the most expressed genes (median = 37.85%, IQR: 30.10-39.49%, p < 0.0001). An in vitro size selection of <150 bp cfDNA could isolate cfDNA representing active genes and the size-selection enrichment correlated with the cfChIP-seq enrichment (Spearman r range: 0.499-0.882, p < 0.0001). This study expands the knowledge regarding cfDNA fragmentomics and sheds new light on how gene activity is associated with both cfDNA fragment lengths and distinct FEMs.

Original languageEnglish
Article number1243
JournalInternational Journal of Molecular Sciences
Number of pages15
Publication statusPublished - Jan 2024


  • Biomarkers, Tumor/genetics
  • Cell-Free Nucleic Acids
  • Humans
  • Liquid Biopsy
  • Lung Neoplasms/genetics
  • liquid biopsies
  • fragmentomics
  • histone modifications
  • gene expression
  • cell-free chromatin immunoprecipitation
  • fragment end motifs


Dive into the research topics of 'Integration of Cell-Free DNA End Motifs and Fragment Lengths Can Identify Active Genes in Liquid Biopsies'. Together they form a unique fingerprint.

Cite this