PT  - JOURNAL ARTICLE
AU  - Joshua Moss
AU  - Roni Ben-Ami
AU  - Ela Shai
AU  - Yosef Kalish
AU  - Agnes Klochender
AU  - Gordon Cann
AU  - Benjamin Glaser
AU  - Ariela Arad
AU  - Ruth Shemer
AU  - Yuval Dor
TI  - Megakaryocyte and erythroblast DNA in plasma and platelets
AID  - 10.1101/2022.10.03.510502
DP  - 2022 Jan 01
TA  - bioRxiv
PG  - 2022.10.03.510502
4099  - http://biorxiv.org/content/early/2022/10/04/2022.10.03.510502.short
4100  - http://biorxiv.org/content/early/2022/10/04/2022.10.03.510502.full
AB  - Circulating cell-free DNA (cfDNA) fragments are a biological analyte with extensive utility in diagnostic medicine. Understanding the source of cfDNA and mechanisms of release is crucial for designing and interpreting cfDNA-based liquid biopsy assays. Using cell type-specific methylation markers as well as genome-wide methylation analysis, we determined that megakaryocytes, the precursors of anuclear platelets, are major contributors to cfDNA (∼26%), while erythroblasts contribute 1-4% of cfDNA in healthy individuals. Surprisingly, we discovered that platelets contain genomic DNA fragments originating in megakaryocytes, contrary to the general understanding that platelets lack genomic DNA. Megakaryocyte-derived cfDNA is increased in pathologies involving increased platelet production (Essential Thrombocythemia, Idiopathic Thrombocytopenic Purpura) and decreased upon reduced platelet production due to chemotherapy-induced bone marrow suppression. Similarly, erythroblast cfDNA is reflective of erythrocyte production and is elevated in patients with Thalassemia. Megakaryocyte- and erythroblast-specific DNA methylation patterns can thus serve as novel biomarkers for pathologies involving increased or decreased thrombopoiesis and erythropoiesis, which can aid in determining the etiology of aberrant levels of erythrocytes and platelets.GRAPHICAL ABSTRACT Competing Interest StatementJM, RS, BG, and YD are inventors of a patent filing describing analysis of platelet DNA as well as megakaryocyte methylation markers and their use for cfDNA analysis. All remaining authors have declared no conflicts of interest.