SARS-CoV-2 spike protein may activate human endogenous retroviruses

A new preprint (yet to be peer-reviewed) paper has been published on medRxiv regarding the discovery.

From exposure to a host of different viruses over humanity's evolution, transposons, DNA segments that can jump from one section of DNA to another, have incorporated viral DNA into our genome. These sections of viral DNA in our genome are collectively known as Human Endogenous Retrovirus (HERV) encoding sequences and comprise about 8% of the human genome.

That equates to about four times more DNA than the amount dedicated to protein-coding genes. Your body uses measures such as DNA methylation and RNA binding to suppress the harmful results from some of these sequences.

This new paper provides evidence for the ability of the spike proteins covering SARS-CoV-2 particles to activate the envelope (ENV) protein, encoded for by the Human Endogenous Retrovirus-W (HERV-W), which in turn leads to many of the symptoms of the disease. Sequences encoding for HERV-W comprise about 1% of the human genome.

Researchers had previously noticed a correlation between the expression of the HERV-W ENV protein and severe respiratory distress in SARS-CoV-2 patients. The study found that only twenty to thirty percent of patients showed significant HERV-W ENV activation, indicating a potential genetic susceptibility among some patients that will need to be explored further. Researchers will now be striving to determine how SARS-CoV-2 activates HERVs.

"Our data suggest that HERV-W ENV is likely to be involved in pathogenic features underlying symptoms of acute and post-acute COVID. It highlights the importance to further understand patients' genetic susceptibility to HERV-W activation and the relevance of this pathogenic element as a prognostic marker and a therapeutic target in COVID-19 associated syndromes," the authors wrote.

You can read more from the paper here.