Interplay between the Genetics of Personality Traits, severe Psychiatric Disorders, and COVID-19 Host Genetics in the Susceptibility to SARS-CoV-2 Infection

Background The SARS-CoV-2 pandemic, with all its impacts on our way of life, is affecting our experiences and mental health. Notably, individuals with mental disorders have been reported to have a higher risk of contracting SARS-CoV-2. Personality traits could represent an important determinant of preventative health behavior and, therefore, the risk of contracting the virus. Aims We examined overlapping genetic underpinnings between major psychiatric disorders, personality traits, and susceptibility to SARS-CoV-2 infection. Methods Linkage disequilibrium score regression was used to explore the genetic correlations of COVID-19 susceptibility with psychiatric disorders and personality traits based on data from the largest available respective genome-wide association studies (GWAS). In two cohorts (the PsyCourse (n=1346) and the HeiDE (n=3266) study), polygenic risk scores were used to analyze if a genetic association between, psychiatric disorders, personality traits, and COVID-19 susceptibility exists in individual-level data. Results We observed no significant genetic correlations of COVID-19 susceptibility with psychiatric disorders. For personality traits, there was a significant genetic correlation for COVID-19 susceptibility with extraversion (p=1.47x10-5; rg=0.284). Yet, this was not reflected in individual-level data from the PsyCourse and HeiDE studies. Conclusions We identified no significant correlation between genetic risk factors for severe psychiatric disorders and genetic risk for COVID-19 susceptibility. Among the personality traits, extraversion showed evidence for a positive genetic association with COVID-19 susceptibility, in one but not in another setting. Overall, these findings highlight a complex contribution of genetic and non-genetic components in the interaction between COVID-19 susceptibility and personality traits or mental disorders.