A NEW study has revealed that mutated genes inherited from Neanderthals doubled the risk of severe Covid in South Asians, The Telegraph reported.
- The report added that these genes, which protected people from smallpox, could be the reason some ethnic groups are more at risk from Covid.
- South Asians in the UK have been at greater risk of severe Covid, even when accounting for factors like deprivation, jobs and living conditions.
- According to the research by Dr Hugo Zeberg, of the Max Planck Institute for Evolutionary Anthropology in Germany, the mutated genes lower the risk of HIV by about 27 per cent.
He also found that they would also prevent other diseases that enter cells in the same way, such as smallpox, The Telegraph report added.
Genetic Analysis
Around half of South Asians carry the mutations, compared to one-fifth of Europeans. According to Dr Zeberg, the variants must have been beneficial at one time in order for them to be passed on.
“This major genetic risk factor for Covid-19 is so common that I started wondering whether it might actually be good for something, such as providing protection against another infectious disease”, Dr Zeberg was quoted as saying by The Telegraph.
“We don't know at the moment why it was likely advantageous 10,000 years ago. There are many genes involved in the immune system in this region of the genome, so there are many plausible candidate genes. If I were to guess, smallpox would be a good candidate. It also enters cells using chemokine receptors. But at this point, this is just speculation.”
Some people become seriously ill when infected with coronavirus while others have only mild symptoms or no symptoms at all.
The study pointed out that genes also contribute to the chances of ending up with a severe Covid infection along with risk factors such as advanced age and other illnesses like diabetes.
People with the Neanderthal mutation on chromosome three have fewer CCR5 receptors which HIV uses to enter human cells, the same entry method as smallpox.
Dr Zeberg added: "A genetic variant can be both good and bad news: Bad news if a person contracts Covid-19, good news because it offers protection against getting infected with HIV.
“Now we know that this risk variant for Covid-19 provides protection against HIV. But it was probably protection against yet another disease that increased its frequency after the last ice age.”
The research was published in the Proceedings of the National Academy of Sciences.