New research by scientists at the Max Planck Institute for Evolutionary Anthropology (MPI-EVA) in Germany and the Karolinska Institute in Sweden shows that the same genetic variant that increases the risk of developing the severe form of Covid-19 reduces the likelihood by 27%. Infection with HIV – reports an article published in the Galileo Journal.

In the second half of 2020, Hugo Seiberg, a researcher at Karolinska Institutet and MPI-EVA, and Svante Pääbo, also at MPI-EVA, found that several people inherited the key genetic factor for Covid-19 from Neanderthals.

According to Galileo Magazine, in the first half of 2021, the pair studied this variant based on a sample of ancient human DNA and determined that its frequency had increased dramatically since the last Ice Age. The gene mutation in question has become very common, which may have been positive in some way in the past.

“(…) I began to wonder if it could really be useful for something, such as providing protection against another infectious disease,” said Hugo Seiberg, in report.

This genetic risk factor is located in the region of chromosome 3 that contains multiple genes encoding immune system receptors. HIV uses one of these receptors, CCR5, to infect white blood cells.

Zberg found that individuals who carry the risk factor for Covid-19 have fewer CCR5 receptors. This led the academic to investigate whether these people would be less likely to contract HIV.

By analyzing patient data from three biobanks (FinnGen, UK Biobank, and Michigan Genomic Initiative), the investigator determined that carriers of the SARS-CoV-2 risk variant had a 27% lower risk of HIV infection.

“This shows how a genetic variant can be good news and bad news: bad news if a person gets infected with Covid-19, that’s good news because it provides protection against HIV infection,” Zyberg wonders.

Also, considering that AIDS only appeared in the 20th century, the researcher notes: “We now know that this risk variant of SARS-CoV-2 provides protection against HIV. But it may have served as protection against another disease that increased in frequency. after the last ice age.