Angiotensin-converting enzyme (ACE1, ACE2) gene variants are associated with COVID19 severity depending on the hypertension status.

BackgroundThe Angiotensin system is implicated in the pathogenesis of COVID19. First, ACE2 is the cellular receptor for SARS-COv-2, and expression of the ACE2 gene could regulate the individuals susceptibility to infection. In addition, the balance between ACE1 and ACE activity has been implicated in the pathogenesis of respiratory diseases and could play a role in the severity of COVID19. Functional ACE1/ACE2 gene polymorphisms have been associated with the risk of cardiovascular and pulmonary diseases, and could thus also contribute to the outcome of COVID19. MethodsWe studied 204 COVID19 patients (137 non-severe and 67severe-ICU cases) and 536 age-matched controls. The ACE1 insertion/deletion and ACE2rs2285666 polymorphism were determined. Variables frequencies were compared between the groups by logistic regression. We also sequenced the ACE2 coding nucleotides in a group of patients. ResultsSevere COVID19 was associated with hypertension male gender (p<0.001), hypertension (p=0.006), hypercholesterolaemia (p=0.046), and the ACE1-DD genotype (p=0.049). In the multiple logistic regression hypertension (p=0.02, OR=2.26, 95%CI=1.12-4.63) and male gender (p=0.002; OR=3.15, 95%CI=1.56-6.66) remained as independent significant predictors of severity. The ACE2 polymorphism was not associated with the disease outcome. The ACE2 sequencing showed no coding sequence variants that could explain an increased risk of developing COVID19. ConclusionsAdverse outcome of COVID19 was associated with male gender, hypertension, hypercholesterolemia and the ACE1 genotype. The ACE1-I/D was a significant risk factor for severe COVID19, but the effect was dependent on the hypertensive status.

Capillary Electrophoresis of PCR fragments with labelled primers for testing the SARS-Cov-2

BackgroundDue to the huge demand for SARS-Cov-2 determination, alternatives to the standard qtPCR tests are potentially useful for increasing the number of samples screened. Our aim was to develop a direct fluorescent PCR capillary-electrophoresis detection of the viral genome. We validated this approach on several SARS-Cov-2 positive and negative samples. Study designWe isolated the naso-pharingeal RNA from 20 positive and 10 negative samples. The cDNA was synthesised and two fragments of the SARS-Cov-2 were amplified. One of the primers for each pair was 5-end fluorochrome labelled. The amplifications were subjected to capillary electrophoresis in ABI3130 sequencers to visualize the fluorescent peaks. ResultsThe two SARS-Cov-2 fragments were successfully amplified in the positive samples, while the negative samples did not render fluorescent peaks. ConclusionWe describe and alternative method to identify the SARS-Cov-2 genome that could be scaled to the analysis of approximately 100 samples in less than 5 hours. By combining a standard PCR with capillary electrophoresis our approach would overcome the limits imposed to many labs by the qtPCR (lack of reactive and real-time PCR equipment) and increase the testing capacity.