Circulating nuclear DNA structural features, origins, and complete size profile revealed by fragmentomics.
JCI Insight
; 6(7)2021 04 08.
Article
en En
| MEDLINE
| ID: mdl-33571170
To unequivocally address their unresolved intimate structures in blood, we scrutinized the size distribution of circulating cell-free DNA (cfDNA) using whole-genome sequencing (WGS) from both double- and single-strand DNA library preparations (DSP and SSP, n = 7) and using quantitative PCR (Q-PCR, n = 116). The size profile in healthy individuals was remarkably homogenous when using DSP sequencing or SSP sequencing. CfDNA size profile had a characteristic nucleosome fragmentation pattern. Overall, our data indicate that the proportion of cfDNA inserted in mono-nucleosomes, di-nucleosomes, and chromatin of higher molecular size (>1000 bp) can be estimated as 67.5% to 80%, 9.4% to 11.5%, and 8.5% to 21.0%, respectively. Although DNA on single chromatosomes or mono-nucleosomes is detectable, our data revealed that cfDNA is highly nicked (97%-98%) on those structures, which appear to be subjected to continuous nuclease activity in the bloodstream. Fragments analysis allows the distinction of cfDNA of different origins: first, cfDNA size profile analysis may be useful in cfDNA extract quality control; second, subtle but reliable differences between metastatic colorectal cancer patients and healthy individuals vary with the proportion of malignant cell-derived cfDNA in plasma extracts, pointing to a higher degree of cfDNA fragmentation and nuclease activity in samples with high malignant cell cfDNA content.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Neoplasias Colorrectales
/
Ácidos Nucleicos Libres de Células
Límite:
Adult
/
Female
/
Humans
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Male
/
Middle aged
Idioma:
En
Revista:
JCI Insight
Año:
2021
Tipo del documento:
Article
País de afiliación:
Francia
Pais de publicación:
Estados Unidos