Common variants at 21q22.3 locus influence MX1 gene expression and susceptibility to severe COVID-19

Abstract

The COVID-19 disease, caused by the SARS-Cov-2, presents a heterogeneous clinical spectrum. The risk factors do not fully explain the wide spectrum of disease manifestations, so it is possible that genetic factors could account for novel insights into its pathogenesis. In our previous study, we hypothesized that common variants on chromosome 21, near TMPRSS2 and MX1 genes, may be genetic risk factors associated to the different clinical manifestations of COVID-19. Here, we performed an in-depth genetic analysis of chromosome 21 exploiting the genome-wide association study data including 6,406 individuals hospitalized for COVID-19 and 902,088 controls with European genetic ancestry from COVID-19 Host Genetics Initiative. We found that five single nucleotide polymorphisms (SNPs) within TMPRSS2 and near MX1 gene show suggestive associations (P[≤]1x10-5) with severe COVID-19. All five SNPs replicated the association in two independent cohorts of Asian subjects while two and one out of the 5 SNPs replicated in African and Italian populations, respectively (P[≤]0.05). The minor alleles of these five SNPs correlated with a reduced risk of developing severe COVID-19 and increased level of MX1 expression in blood. Our findings provide further evidence that host genetic factors can contribute to determine the different clinical presentations of COVID-19 and that MX1, an antiviral effector of type I and III interferon pathway, may be a potential therapeutic target.