[BGR] Like any virus, the novel coronavirus mutates, and teams of scientists are keeping track of various strains that are circulating right now. So far, there hasn’t been any meaningful mutation that would make the virus more lethal or compromise existing vaccine research, and that’s good news. However, there is one mutation that’s seen plenty of coverage in the past few months, the D614G strain that’s believed to be more infectious than its predecessors. Some researchers think the mutation allows the virus to hook up to cells more efficiently than before, and that’s what makes it more infectious. But not all mutations will help the SARS-CoV-2 virus. A new study has just been published in a medical journal proposing that a new coronavirus mutation actually results in a milder case of COVID-19.Published in The Lancet (via Medical Express), the study details a coronavirus strain identified as ∆382 that doctors in Singapore studied between January and March, comparing it with other available SARS-CoV-2 strains that were circulating at the time.
The researchers explain that the ∆382 mutation involves the deletion of 382 nucleotides that appears in the open reading frame 8 region (ORF8), which is a known spot for mutations in coronaviruses. As a result, the ORF8 protein is not produced, the researchers said. During the SARS epidemic nearly 20 years ago, a deletion of 29 nucleotides in the ORF8 region resulted in a variant of the virus that was unable to replicate as efficiently as the wild-type SARS virus.
Furthermore, ∆382 patients had lower concentrations of pro-inflammatory cytokines and chemokines that are usually associated with severe COVID-19. They also showed lower levels of growth factors associated with lung injury and regeneration, which implies their lungs were not as damaged.The researchers note that the ∆382 groups also showed a better immune response to the virus, including more effective platelet regulation and T cell responses early in the infection. The patients also showed a more robust production of a cytokine called IFN-γ, which could explain the heightened immune response. Interestingly, the observations held true even when taking age groups and comorbidities into account. The researchers think this version of the virus triggers a reduced pro-inflammatory response and a less-damaging cytokine storm, which results in a milder COVID-19 case.
The researchers speculate that the absence of the ORF8 protein inhibits the virus’s ability to evade the immune system, but more research is needed to demonstrate these findings.
More research; there must be more research!
Even if the ∆382 mutation does cause a less severe version of COVID-19, there's no telling what one's chances are of getting infected with that milder strain instead of a more lethal version. But if the ORF8 hypothesis is correct and drugs can target the protein, doctors may be able to develop new therapies that can reduce COVID-19 complications.