- Several risk factors have been associated with severe coronavirus illness, and health officials have a good idea about which patients are likely to develop symptoms and complications after infection.
- It’s still unclear why the coronavirus affects some people more severely than others, and why many people deal with mild to moderate cases of COVID-19.
- A new study that’s yet to be peer-reviewed says that a segment containing genes inherited from Neanderthals 60,000 years ago can be associated with an increased risk of severe COVID-19 cases.
Not all of the people who test positive for the novel coronavirus will experience a bad case of COVID-19 requiring oxygen therapy or mechanical ventilation. That’s something many people will say in order to minimize the ongoing surge in cases. That is somewhat true. Some will not realize they carry the disease, and others will experience a milder version of COVID-19. A wide variety of patients are at risk of developing severe illnesses, but that doesn’t guarantee that everyone else will survive. Once you start showing symptoms, there’s no telling which way the disease will go, even if you don’t have any medical conditions that can complicate the disease.
Doctors are still trying to understand why COVID-19 is a more significant threat to old people suffering from certain preexisting conditions and why men are more likely to die than women of the same age. And physicians have discovered therapies that can lower the COVID-19 death rate for patients who do go on ventilators, but the fatality percentage remains high. Amid the ongoing coronavirus research, genetics stand out.
The science can keep track of coronavirus mutation, but also try to explain the risk factors at the gene level for severe COVID-19 cases. A new paper did just that, and the conclusion is incredible: It’s the Neanderthal in you that could be responsible for an increased risk of developing a severe case of coronavirus.
About 60,000 years ago, some ancestors of modern humans expanded from Africa to Europe, Asia, and Australia, explains The New York Times. It’s then that they met Neanderthals and interbred. The exchange led to new humans who inherited genes from both parents. Most of the Neanderthal genes went away as they were harmful to modern humans. But a specific set of genes turned out to be useful.
These genes protected against viruses found in the new regions those ancestors explored. The Neanderthals had already been exposed to those pathogens, hence the genes. And it turns out that the Neanderthal genes that could have prevented epidemics in the distant past may be responsible for COVID-19 complications.
Scientists published their new findings online in bioRxiv, but the study hasn’t been peer-reviewed
Dr. Hugo Zeberg and Dr. Svante Paabo think that six genes on Chromosome 3 may be responsible for increased risk for severe illnesses. This sequence is common in Bangladesh, where 63% of people carry at least one copy. One-third of South Asian people have inherited the segment as well.
People of Bangladeshi descent are dying at a high rate in the UK, The Times note. This finding could explain why they’re more likely to experience complications. The gene sequence is less common in Europe (8%) and East Asia (4%). It’s almost absent in Africa. But it’s unclear what caused this distribution. “That’s the $10,000 question,” Zeberg told The Times. “One should stress that at this point this is pure speculation,” Paabo said about the study.
The research shows a strong link between COVID-19 and the Chromosome 3 segment. People who carry two copies of the variant are three times more likely to experience a severe form of COVID-19.
After the results came out last week, Zeberg studied a database of Neanderthal genes and found that the Chromosome 3 sequence is identical to a version found in a Neanderthal who lived in Croatia some 50,000 years ago.
The Times notes that one theory that can explain the finding is that the genes the modern human kept from Neanderthals helped the race fight disease. The genes could be responsible for the immune system’s overreaction. It’s that exacerbated immune response that doctors attempt to control to save lives following COVID-19 complications.
It’s unclear how this discovery can be used to improve the treatment of COVID-19 and prevent the transmission of the novel coronavirus. But it’s still a finding that’s worth investigating.