A year of Covid-19 GWAS results from the GRASP portal reveals potential SARS-CoV-2 modifiers

Host genetic variants influence the susceptibility and severity of several infectious diseases, and the discovery of novel genetic associations with Covid-19 phenotypes could help developing new therapeutic strategies to reduce its burden.

Between May 2020 and June 2021, we used Covid-19 data released periodically by UK Biobank and performed 65 Genome-Wide Association Studies (GWAS) in up to 18 releases of Covid-19 susceptibility (N=18,481 cases in June 2021), hospitalization (N=3,260), severe outcomes (N=1,244) and death (N=1,104), stratified by sex and ancestry.

In coherence with previous studies, we observed 2 independent signals at the chr3p21.31 locus (rs73062389-A, OR=1.21, P=4.26×10⁻¹⁵ and rs71325088-C, OR=1.62, P=2.25×10⁻⁹) modulating susceptibility and severity, respectively, and a signal influencing susceptibility at the ABO locus (rs9411378-A, OR=1.10, P=3.30×10⁻¹²), suggesting an increased risk of infection in non-O blood groups carriers. Additional signals at the APOE (associated with severity and death) LRMDA (susceptibility in non-European) and chr2q32.3 (susceptibility in women) loci were also identified but did not replicate in independent datasets. We then devised an original approach to extract variants exhibiting an increase in significance over time. When applied to the susceptibility, hospitalization and severity analyses, this approach revealed the known DPP9, RPL24 and MAPT loci, amongst thousands of other signals. Finally, this significance trajectory analysis was applied to the larger Covid-19hgi meta-analyses, where additional loci of interest, related to the immune system, were identified.

These results, freely available on the GRASP portal, provide new insights on the genetic mechanisms involved in Covid-19 phenotypes.