Genetic association between LONG COVID and TMPRSS2 polymorphisms (rs12329760 and rs2070788) in Brazilian healthcare...

Long COVID syndrome has a multifactorial cause that is not fully understood and may be influenced by both external and intrinsic factors. In this context, a Genome-Wide Association Study (GWAS) was proposed to evaluate the association between Single Nucleotide Polymorphisms (SNPs) in TMPRSS2 (rs12329760 and rs2070788) and the occurrence of Long COVID in 363 Brazilian healthcare professionals, recruited using a non-probabilistic method. The study employed a self-report questionnaire to collect sociodemographic and clinical data from both the acute and chronic phases and also collected oral mucosa cells for genotypic analysis by qPCR using Taqman probes. The categorized information was analyzed using the PSPP software using Pearson's chi-square test in three genetic statistical models: additive, dominant, and recessive. Assessing long COVID in general, only clinical variables such as increased susceptibility, presence of symptoms, and severity influenced the occurrence of the syndrome. When specifying the main reported symptom, brain fog, females and young adults (18 to 29 years old) are the most vulnerable, and rs2070788 in the recessive model proved to be relevant. This association is more evident when evaluating only the symptomatic group in the post-COVID period, as the additive model also influences the groups. rs12329760 showed no relevant influence on the groups. Therefore, this study provides unprecedented evidence of the association between brain fog and rs2070788, requiring case-control studies to better clarify how this association occurs.