Elevated brain-derived cell-free DNA among patients with first psychotic episode - a proof-of-concept study

  1. Asael Lubotzky
  2. Ilana Pelov
  3. Ronen Teplitz
  4. Daniel Neiman
  5. Adama Smadja
  6. Hai Zemmour
  7. Sheina Piyanzin
  8. Bracha Lea Ochana
  9. Kirsty L Spalding
  10. Benjamin Glaser
  11. Ruth Shemer  Is a corresponding author
  12. Yuval Dor  Is a corresponding author
  13. Yoav Kohn  Is a corresponding author
  1. The Hebrew University-Hadassah Medical School, Israel
  2. Jerusalem Mental Health Center, Israel
  3. Karolinska Institutet Innovations, Sweden
  4. Hebrew University of Jerusalem, Israel

Abstract

Schizophrenia is a common, severe and debilitating psychiatric disorder. Despite extensive research there is as yet no biological marker that can aid in its diagnosis and course prediction. This precludes early detection and intervention. Imaging studies suggest brain volume loss around the onset and over the first few years of schizophrenia, and apoptosis has been proposed as the underlying mechanism. Cell-free DNA fragments (cfDNA) are released into the bloodstream following cell death. Tissue-specific methylation patterns allow the identification of the tissue origins of cfDNA. We developed a cocktail of brain specific DNA methylation markers, and used it to assess the presence of brain-derived cfDNA in the plasma of patients with a first psychotic episode. We detected significantly elevated neuron- (p=0.0013), astrocyte- (p=0.0016), oligodendrocyte- (p=0.0129) and whole brain-derived (p=0.0012) cfDNA in the plasma of patients during their first psychotic episode (n=29), compared with healthy controls (n=31). Increased cfDNA levels were not correlated with psychotropic medications use. Area Under the Curve (AUC) was 0.77, with 65% sensitivity at 90% specificity in patients with a psychotic episode. Potential interpretations of these findings include increased brain cell death, disruption of the blood-brain barrier or a defect in clearance of material from dying brain cells. Brain-specific cfDNA methylation markers can potentially assist early detection and monitoring of schizophrenia and thus allow early intervention and adequate therapy.

Data availability

All relevant data including information on the markers used (coordinates and primer sequences), detailed information on patients and donors and the raw data on values of each methylation marker in each sample is provided in Source data 1. This data was used to generate the graphs shown in the paper.Detailed PCR conditions are detailed in the Materials and methods section and were published in a recent paper. Code is uploaded to GitHub as described in the paper (https://github.com/Joshmoss11/btseq).

Article and author information

Author details

  1. Asael Lubotzky

    Department of Developmental Biology and Cancer Research, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0460-0084
  2. Ilana Pelov

    Eitanim Psychiatric Hospital, Jerusalem Mental Health Center, Jerusalem, Israel
    Competing interests
    No competing interests declared.
  3. Ronen Teplitz

    Eitanim Psychiatric Hospital, Jerusalem Mental Health Center, Jerusalem, Israel
    Competing interests
    No competing interests declared.
  4. Daniel Neiman

    Department of Developmental Biology and Cancer Research, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
    Competing interests
    Daniel Neiman, has filed patents on cfDNA analysis technology (year 2019, application number 62/828,587).
  5. Adama Smadja

    Department of Developmental Biology and Cancer Research, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
    Competing interests
    No competing interests declared.
  6. Hai Zemmour

    Department of Developmental Biology and Cancer Research, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
    Competing interests
    Hai Zemmour, has filed patents on cfDNA analysis technology (year 2019, application number 62/828,587).
  7. Sheina Piyanzin

    Department of Developmental Biology and Cancer Research, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
    Competing interests
    No competing interests declared.
  8. Bracha Lea Ochana

    Department of Developmental Biology and Cancer Research, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
    Competing interests
    No competing interests declared.
  9. Kirsty L Spalding

    Department of Cell and Molecular Biology, Karolinska Institutet Innovations, Stockholm, Sweden
    Competing interests
    No competing interests declared.
  10. Benjamin Glaser

    6Department of Endocrinology and Metabolism Service, Hebrew University of Jerusalem, Jerusalem, Israel
    Competing interests
    Benjamin Glaser, has filed patents on cfDNA analysis technology (year 2019, application number 62/828,587).
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4711-5000
  11. Ruth Shemer

    Department of Developmental Biology and Cancer Research, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
    For correspondence
    shemer.ru@mail.huji.ac.il
    Competing interests
    Ruth Shemer, has filed patents on cfDNA analysis technology (year 2019, application number 62/828,587).
  12. Yuval Dor

    Department of Developmental Biology and Cancer Research, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
    For correspondence
    yuvald@ekmd.huji.ac.il
    Competing interests
    Yuval Dor, has filed patents on cfDNA analysis technology (year 2019, application number 62/828,587).
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2456-2289
  13. Yoav Kohn

    Eitanim Psychiatric Hospital, Jerusalem Mental Health Center, Jerusalem, Israel
    For correspondence
    yoavk@ekmd.huji.ac.il
    Competing interests
    No competing interests declared.

Funding

Award of the National Institute of Psychobiology in Israel and the Israeli Society of Biological Psychiatry

  • Asael Lubotzky

Israel Science Foundation

  • Yuval Dor

Grail

  • Yuval Dor

Award of the National Institute of Psychobiology in Israel and the Israeli Society of Biological Psychiatry

  • Ilana Pelov

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Jacky Lam, Chinese University of Hong Kong, Hong Kong

Ethics

Human subjects: This study was conducted according to protocols approved by the Jerusalem Mental Health Center Institutional Review Board, in accordance with the Declaration of Helsinki (HMO-14-0198).We recruited men and women over 18 years of age, who have developed psychotic symptoms for the first time in their life within the last year and were admitted to the acute psychiatric units of the Jerusalem Mental Health Center in Israel.Blood samples were obtained after the initial stabilization and partial remission of the psychotic symptoms which enabled the patients to give written informed consent for participation in the study. The time achieving stability was different for each individual patient, but the majority stabilized within 4 weeks (79%). The patients were asked to complete a short questionnaire regarding demographic details, current physical condition, the onset of present symptoms and drug use. The recruitment was done following the approval of the study's protocol by the Jerusalem Mental Health Center Institutional Review Board. Patients with acute medical conditions in the week prior to the blood sampling were excluded from the study.31 adult volunteers participated in the study as unpaid healthy controls.

Version history

  1. Received: December 15, 2021
  2. Preprint posted: February 10, 2022 (view preprint)
  3. Accepted: June 6, 2022
  4. Accepted Manuscript published: June 14, 2022 (version 1)
  5. Version of Record published: June 16, 2022 (version 2)

Copyright

© 2022, Lubotzky et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Asael Lubotzky
  2. Ilana Pelov
  3. Ronen Teplitz
  4. Daniel Neiman
  5. Adama Smadja
  6. Hai Zemmour
  7. Sheina Piyanzin
  8. Bracha Lea Ochana
  9. Kirsty L Spalding
  10. Benjamin Glaser
  11. Ruth Shemer
  12. Yuval Dor
  13. Yoav Kohn
(2022)
Elevated brain-derived cell-free DNA among patients with first psychotic episode - a proof-of-concept study
eLife 11:e76391.
https://doi.org/10.7554/eLife.76391

Share this article

https://doi.org/10.7554/eLife.76391

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