Investigators at the Riken Institute in Japan developed new computational methods to detect virus induced structural variants in the human genome
New technique for precisely identifying integration site of HHV-6 in telomeres
Using whole genome optical mapping, investigators found that contrary to previous findings, the length of telomeres with viral integration was not unusually short.
Telomeric integration, excision and subsequent and transmission in people with inherited chromosomally integrated HHV-6B (iciHHV-6B)
Exploiting a hypervariable region of the HHV-6B genome, investigators achieve new insights about integration, excision, and genomic stability of iciHHV-6B
Japanese study supports evidence of iciHHV-6 reactivation in vivo
Surprisingly, 72% of integrated genomes were found on chromosome 22q. Solo-DR sequences of HHV-6B were left behind after excision and reactivation.
One step closer to understanding HHV-6A/B chromosomal integration
The mechanisms leading to HHV-6A/B integration are a subject of intense research by several laboratories. A new paper in PLoS Pathogens provides some understanding as to how HHV-6A/B may integrate host chromosomes.
iciHHV-6 may modulate human gene expression
A Japanese group found that ciHHV6 genes encoding for immunoglobulins were decreased in ciHHV6 individuals, possibly modulating immune responses.
Multiplex FilmArray Meningitis/Encephalitis assay is useful for diagnosing HHV-6 encephalitis
This multiplex qualitative test for cerebrospinal fluid helps physicians diagnose HHV-6 encephalitis quickly, but interpretation must take into account imaging, ciHHV-6 status and other markers.
Patients with iciHHV-6 have higher inflammatory cytokines and develop acute graft vs host disease a week earlier
Transplant patients born with chromosomally integrated HHV-6 have elevated levels of C-reactive protein and tumor necrosis factor receptor 1, both markers associated with increased risk of acute graft-versus-host disease.
Spontaneous gene expression in iciHHV-6A/B individuals leads to increased HHV-6 IE-1A/B and CMV antibody response; higher levels of RNA were found in iciHHV-6A brains
A comprehensive study of DNA and RNA-Seq data demonstrated in vivo gene expression in many iciHHV-6 tissues, with strong expression of IE-1 and matching elevated antibody response in iciHHV-6 individuals compared to controls.
Genomic analysis finds a surprising association between ciHHV-6 and two genes
A genomic analysis of samples from 141,431 Chinese women found a highly significant association between ciHHV-6 and a variant in the MLCI-MOV10L region. The MLC1 gene is involved in myeloid cell differentiation and the MOV10L1 gene may allow for more efficient integration during spermatogenesis.
Apparent activation of ciHHV-6 in response to HDACi cancer drug vorinostat
Inherited ciHHV-6 has been shown to activate under conditions of immunosuppression and and the pan-HDAC inhibitor TSA activates integrated ciHHV-6 in vitro. This is the first case report of HHV-6 activation in a ciHHV-6 patient who received a pan-HDAC inhibitor drug.
Ancient iciHHV-6 genomes vary considerably from community strains, but still capable of reactivation
British researchers used molecular dating methods to determine that most strains of iciHHV-6 come from a small number of ancient human ancestors; the youngest found lived over 24,000 years ago. These ancient strains vary considerably from modern non-inherited strains of HHV-6A and appear just as likely to activate as their more modern cousins.
Multiple herpesvirus infections lead to telomere shortening
Investigators at Kings College London report that seropositivity for CMV, Herpes simplex 1 and HHV-6 are all associated with a significant shortening of telomeres over a three-year period. Furthermore, the magnitude of the changes was large. For example, CMV seropositivity was associated with the equivalent of almost 12 years of chronological age.
Blood virome sequencing reveals new data on roseolovirus prevalence and epidemiology
Sequencing of over 8,000 individuals were used to determined the prevalence of 94 different viruses. HHV-7 was the most common virus, with HHV-6B and HHV-6A 4th and 5th respectively.
In Japan, inherited ciHHV-6A likely derived from common ancestor
A team in Japan has reports that ciHHV-6A prevalence is influenced by a “founder effect” and is likely derived from a common ancestor. All of the individuals in the small study were found to have HHV-6A integrated into the telomeric region of chromosome 22, a common site of integration.