Coronavirus disease 2019 (COVID-19) is a respiratory syndrome in which affected individuals may present different clinical outcomes, driven by clinical, viral, and host genetic factors. During viral entry, SARS-CoV-2 uses specific invasion mechanisms, and certain proteins are important in this process—especially transmembrane serine protease 2 (TMPRSS2). In this sense, understanding changes in this protein resulting from single nucleotide polymorphisms (SNPs) in its gene is important to assess the influence of host genetics on disease outcomes. The objective of this study was to identify the association of SNPs in the TMPRSS2 gene with clinical outcomes in hospitalized COVID-19 patients. Blood samples were included from 192 individuals positive for COVID-19, aged ≥55 years, hospitalized in two referral centers for the disease in Petrolina, Pernambuco, between August 2020 and July 2021. Genomic DNA was obtained from peripheral blood samples using a commercial extraction kit (ReliaPrep™ Blood gDNA Miniprep System – Promega). For genotyping, real-time PCR methodology was used with the TaqMan probe system (Thermo Scientific), adopting probes rs2070790, rs4290734, and rs2070788 (Applied Biosystems). Statistical analyses were performed using Jasp (v. 0.19.3.0), in which the chi-square value (X²) was calculated, considering results significant when p < 0.05. The study analyzed clinical outcomes of 143 recovered patients and 49 deaths. In both groups, there was a predominance of males. In genotypic analysis of the SNPs, an association was verified for rs2070790 (X² = 7.534; p = 0.023) with genotype distribution of CC = 91.67%; CG = 78.49% and GG = 66.30% in recovered patients and CC = 8.33%; CG = 21.51% and GG = 33.70% in deaths; for rs4290734 (X² = 10.868; p = 0.004) with genotype distribution of AA = 85.89%, AG = 65.90% and GG = 61.11% in recovered patients and AA = 14.11%, AG = 34.10% and GG = 38.89% in deaths; and for rs2070788 (X² = 8.244; p = 0.016) with genotype distribution of AA = 84.74%, AG = 74.00% and GG = 57.58% in recovered patients and AA = 15.26%, AG = 26.00% and GG = 42.42% in deaths. Based on these results, it was possible to observe an association of polymorphisms rs2070790, rs4290734, and rs2070788 in the TMPRSS2 gene with clinical outcomes in older hospitalized COVID-19 patients.
Silva et al. (Sun,) studied this question.