Infectious diseases: Genetic risk factor for severe COVID-19 may be inherited from Neanderthals

Genetic variants that are associated with the risk of severe COVID-19 may have been inherited from Neanderthals, reports a paper published in Nature. This is just one of many risk factors for severe disease, others include advanced age and being male.

Previous research has identified a gene cluster on chromosome 3 that is associated with respiratory failure upon infection with SARS-CoV-2. To determine the origins of the gene cluster, Hugo Zeberg and Svante Pääbo analysed the ancient genomes of Neanderthals and Denisovans (ancient hominins that contributed genetic variants to early modern humans). 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 an approximately 50,000-year-old Neanderthal from Croatia, southern Europe. This haplotype is present in around 16% of the population in Europe and 50% of people in South Asia.

The highest frequency occurs in Bangladesh, where 63% of the population are estimated to carry at least one copy of the Neanderthal risk haplotype. The varying prevalence of this risk haplotype may contribute to the differences in severity of COVID-19 that have been observed between different populations. For example, individuals of Bangladeshi descent in the UK have about two times higher risk of dying from COVID-19 than the general population, the authors note.