Jiang P et al., Cell Genomics - This episode reviews a Cell Genomics study that uses ssDNA '2-end' and novel '4-end' sequencing to profile native 5′ and 3′ termini of plasma cfDNA. The work identifies PREM/POEM markers, links 3′ ends to methylation, and shows improved HCC detection. Key terms: cfDNA fragmentomics, 3' end motifs, 4-end sequencing, hepatocellular carcinoma, DNASE1L3.

Study Highlights:
The authors adapted single-stranded library preparation (2-end sequencing) to measure native 5′ (EM5) and 3′ (EM3) end motifs and defined flanking PREM and POEM motifs. Combining size‑stratified PREM, EM5, EM3, and POEM features raised hepatocellular carcinoma (HCC) detection to an AUC of 0.95. Fragmentomics-based methylation analysis of 3′ ends (3′ FRAGMA) improved HCC detection further (AUC 0.97). A novel 4-end sequencing approach captured all four termini of double‑stranded cfDNA, yielding 4‑end motif models with AUC up to 0.98 and revealing coordinated nuclease activity, notably DNASE1L3 involvement.

Conclusion:
Holistic end profiling of cfDNA—integrating native 5′ and 3′ ends, flanking motifs, methylation-informed fragmentomics, and four‑end resolution—enhances cancer detection performance and provides mechanistic insight into coordinated nuclease-mediated fragmentation, warranting larger validation studies.

Music:
Enjoy the music based on this article at the end of the episode.

Article title:
Holistic determination of ends of cfDNA molecules

First author:
Jiang P

Journal:
Cell Genomics

DOI:
10.1016/j.xgen.2026.101142

Reference:
Jiang P., Ma M.-J. L., Qiao R., et al. Holistic determination of ends of cfDNA molecules. Cell Genomics. 2026;6:101142. doi:10.1016/j.xgen.2026.101142

License:
This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/

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Episode link: https://basebybase.com/episodes/holistic-cfdna-ends-episode-333

QC:
This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-04-04.

QC Scope:
- article metadata and core scientific claims from the narration
- excludes analogies, intro/outro, and music
- transcript coverage: Audited the transcript’s substantive description of 2-end sequencing (EM5/EM3), PREM/POEM, 3'-FRAGMA, 4-end sequencing, nuclease signatures (DNASE1L3, DNASE1, DFFB), HCC diagnostic performance (AUC values), fragment-size context, and translational limitations as reported in the article.
- transcript topics: 2-end sequencing preserving native ends (EM5/EM3); Pre-end (PREM) and post-end motifs (POEM); 4-end sequencing with stem-loop adapters and PacBio SMRT; 3'-FRAGMA methylation analysis; Nuclease-specific end motifs and coordinated fragmentation (DNASE1L3, DNASE1, DFFB); HCC detection performance and AUC values

QC Summary:
- factual score: 10/10
- metadata score: 10/10
- supported core claims: 8
- claims flagged for review: 0
- metadata checks passed: 4
- metadata issues found: 0

Metadata Audited:
- article_doi
- article_title
- article_journal
- license
- episode_title
- episode_number
- season

Factual Items Audited:
- 2-end sequencing preserves native 5' and 3' ends (EM5/EM3) by omitting end-repair during library prep
- PREM and POEM motifs are defined and analyzed as end-motif neighbors around EM5 and EM3
- 4-end sequencing enables simultaneous assessment of all four termini using stem-loop adapters and PacBio SMRT sequencing
- 3'-FRAGMA shows methylation-associated fragmentation patterns and improves HCC detection (AUC 0.97)
- Combined end-motif analysis across PREM, EM5, EM3, and POEM yields AUC ≈ 0.95 for HCC detection
- DNASE1L3 identified as a major contributor to cfDNA fragmentation; DNASE1L3 knockout mice alter motif frequencies

QC result: Pass.