Variation in human herpesvirus 6B telomeric integration, excision and transmission between tissues and individuals
- University of Leicester, United Kingdom
- MRC-University of Glasgow Centre for Virus Research, United Kingdom
- University of Groningen, Netherlands
- University of Manchester, United Kingdom
- Centre hospitalier de l'Université Laval, Canada
Abstract
Human herpesviruses 6A and 6B (HHV-6A/6B) are ubiquitous pathogens that persist lifelong in latent form and can cause severe conditions upon reactivation. They are spread by community-acquired infection of free virus (acqHHV6A/6B) and by germline transmission of inherited chromosomally-integrated HHV-6A/6B (iciHHV-6A/6B) in telomeres. We exploited a hypervariable region of the HHV-6B genome to investigate the relationship between acquired and inherited virus and revealed predominantly maternal transmission of acqHHV-6B in families. Remarkably, we demonstrate that some copies of acqHHV-6B in saliva from healthy adults gained a telomere, indicative of integration and latency, and that the frequency of viral genome excision from telomeres in iciHHV-6B carriers is surprisingly high and varies between tissues. In addition, newly formed short telomeres generated by partial viral genome release are frequently lengthened, particularly in telomerase-expressing pluripotent cells. Consequently, iciHHV-6B carriers are mosaic for different iciHHV-6B structures, including circular extra-chromosomal forms that have the potential to reactivate. Finally, we show transmission of an HHV-6B strain from an iciHHV-6B mother to her non-iciHHV-6B son. Altogether we demonstrate that iciHHV-6B can readily transition between telomere-integrated and free virus forms.
Data availability
Sequencing data have been deposited in GenBank under accession numbers: MW049313-MW049327.The HHV6 explorer is freely available at https://www.hhv6explorer.org/ and so The source code for the HHV6 explorer and HHV6 counter are available at https://github.com/colinveal/HHV6-Explorer.Other data generated or analysed during this study are included in the manuscript and supporting files.
Article and author information
Author details
Funding
Biotechnology and Biological Sciences Research Council (MIBTP 1645656)
- Michael L Wood
Medical Research Council (G0901657)
- Nicola J Royle
HHV-6 Foundation (Pilot grant)
- Nicola J Royle
Canadian Institutes of Health Research (MOP 123214)
- Louis Flamand
European Commission (FP7-242209- BIOSTAT-CHF)
- Adriaan A Voors
Medical Research Council (MC_UU_12014/3)
- Andrew J Davison
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: The study was conducted in accordance with the Declaration of Helsinki and with approval by the relevant ethics committees as follows:The University of Leicester's Research Ethics Committee (refs: 10553-njr-genetics; njr-61d3).The BIOSTAT-CHF study was approved by the relevant ethics committee in each centre, all participants gave their written, informed consent to participate (Voors et al, 2016).
Copyright
© 2021, Wood 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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Variation in human herpesvirus 6B telomeric integration, excision and transmission between tissues and individuals
eLife 10:e70452.
https://doi.org/10.7554/eLife.70452
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