The genetic variants that are associated with the highest risk of severe COVID-19 may have been inherited from Neanderthals, says an article published in Nature. This is just one of many risk factors for serious disease, others include older age and male gender.
Previous research has identified a group of genes on chromosome 3 that is associated with respiratory failure after SARS-CoV-2 infection.
To determine the origins of the gene pool, Hugo Zeberg and Svante Pääbo, from the Max Planck Institute of Anthropology, analyzed the ancient genomes of Neanderthals and Denisovans (ancient hominins that contributed genetic variants to early modern humans).
In this way they discovered that the genetic variants in this region are derived from a large group of genes (known as a haplotype) that have been inherited from Neanderthals. This haplotype is most closely related to a approximately 50,000-year-old Neanderthal from Croatia, southern Europe. This haplotype is present in around 16% of the population in Europe and in 50% of people in South Asia.
The highest frequency occurs in Bangladesh, where it is estimated that the 63% of the population carry at least one copy of the haplotype Neanderthal risk. The variable prevalence of this risk haplotype may contribute to the differences in severity of COVID-19 that have been observed between different populations.
For example, people from Bangladeshi descent in the UK they have approximately twice the risk of dying from COVID-19 than the general population, the authors note.