Study of frequency and inheritance model of ACE1 I/D and ACE2 rs2285666 polymorphisms in COVID-19 patients with varying severity of lung involvement and its effect on serum cytokines levels

The first assessment of Angiotensin-Converting Enzyme 1 (ACE1) D/I polymorphism and demographic factors in association with COVID-19 outcomes in the Moroccan Population

BACKGROUND

SARS-CoV-2 responsible for the COVID-19 pandemic, infiltrates the human body by binding to the ACE2 receptor in the respiratory system cell membranes, leading to severe lung tissue damage. An analog of ACE2, ACE1, has gained attention due to its well-known Deletion/Insertion (D/I) polymorphism, which seems to be associated with COVID-19 outcomes. This study aims to reveal the allelic and genotypic frequencies of the rs4646994 polymorphism in the Moroccan population and investigate the association between COVID-19 outcomes and both genotypic and demographic data.

METHODS AND RESULTS

We screened 162 Moroccan COVID-19 patients for the ACE1 gene D/I polymorphism using PCR amplification of the ACE1 polymorphic region within intron 16. Statistical analysis of the relationship between COVID-19 outcomes and each of the genetic and demographic data was performed using R software. The D allele was present in 74% of subjects. Homozygous (II) and heterozygous (DI) genotypes for the Insertion allele were present in 41.4% and 5.6% of patients, respectively. The median age in the COVID-19 'critical symptoms' category was significantly higher and gradually decreased with less severe symptoms. Similarly, males were significantly overrepresented in the 'critical symptoms' category, while females predominated in the 'mild symptoms' category.

CONCLUSIONS

The present study reports the prevalence of ACE1 D/I alleles for the first time in the Moroccan population and confirms the strong association of severe COVID-19 outcomes with male sex and older age. Moreover, this work is the first to explore the relationship between ACE1 D/I polymorphism and COVID-19 clinical outcomes in North African adults. The lack of a significant association may be due to cohort size or population-specific factors. A comprehensive investigation in a larger North African cohort is highly recommended.

Insertion/deletion (I/D) polymorphisms of angiotensin-converting enzyme gene and their implications for susceptibility and severity of COVID-19: A systematic review and meta-analysis

The insertion or deletion polymorphisms of the angiotensin-converting enzyme gene (ACE I/D) have been the subject of significant research related to coronavirus disease 2019 (COVID-19). Despite this, the findings have remained uncertain and debatable. The aim of this study was to determine the associations between the ACE I/D polymorphisms and the susceptibility as well as the severity of COVID-19. A meta-analysis study (PROSPERO: CRD42022384562) was conducted by searching the articles published on PubMed, Scopus, and Embase as of May 15, 2023. Information regarding the impact of ACE I/D variant on the susceptibility to COVID-19 and its severity was collected and analyzed utilizing the Mantel-Haenszel method with a random effects model or fixed effects model, depending on the presence or absence of heterogeneity. Out of 3,335 articles, 21 articles were included, of which 13 investigated the association between ACE I/D and the risk of COVID-19 infection and 18 of them examined its influence on disease severity. The D allele of ACE increased risk of COVID-19 infection (OR: 1.41; 95%CI: 1.08-1.85; p-Egger: 0.0676; p-Heterogeneity: <0.001; p=0.0120), while ACE I allele (OR: 0.71; 95%CI: 0.54-0.93; p-Egger: 0.0676; p-Heterogeneity: <0.001; p=0.012) and II genotype (OR: 0.55; 95%CI: 0.34-0.87; p-Egger: 0.200; p-Heterogeneity: <0.001; p=0.011) decreased the risk of infection. Additionally, there was a notable association between the ACE ID genotype and an elevated likelihood of experiencing severe COVID-19 within the Asian population (OR: 1.46; 95%CI: 1.15-1.84; p-Egger: 0.092; p-Heterogeneity: 0.116; p=0.002). The presence of ACE I/D polymorphisms significantly influences the likelihood of being susceptible to and experiencing the severity of COVID-19.

Angiotensin-Converting Enzyme-2 (ACE-2) with Interferon-Induced Transmembrane Protein-3 (IFITM-3) Genetic Variants and Interleukin-6 as Severity and Risk Predictors among COVID-19 Egyptian Population

Introduction

The host genetic background is a crucial factor that underlies the interindividual variability of COVID-19 fatality and outcomes. Angiotensin-converting enzyme-2 (ACE-2) and interferon-induced transmembrane protein-3 (IFITM-3) have a key role in viral cell entrance and priming. The evoked immune response will also provide a predictive prognosis for COVID-19 infection. This study aimed to explore the association between ACE-2 and IFITM-3 genotypes and their corresponding allele frequencies with disease severity indices in the Egyptian COVID-19 population. The serum level of interleukin-6, as a biomarker of hyperinflammatory response, and cytokine storm, was correlated with disease progression, single nucleotide polymorphisms (SNPs) of the selected receptors, and treatment response. Methodology. We enrolled 900 COVID-19-confirmed cases and 100 healthy controls. Genomic DNA was extracted from 200 subjects (160 patients selected based on clinical and laboratory data and 40 healthy controls). The ACE-2 rs2285666 and IFITM-3 rs12252 SNPs were genotyped using the TaqMan probe allelic discrimination assay, and the serum IL-6 level was determined by ELISA. Logistic regression analysis was applied to analyze the association between ACE-2 and IFITM-3 genetic variants, IL-6 profile, and COVID-19 severity.

Results

The identified genotypes and their alleles were significantly correlated with COVID-19 clinical deterioration as follows: ACE2 rs2285666 CT + TT, odds ratio (95% confidence interval): 12.136 (2.784-52.896) and IFITM-3 rs12252 AG + GG: 17.276 (3.673-81.249), both p < 0.001. Compared to the controls, the heterozygous and mutant genotypes for both SNPs were considerable risk factors for increased susceptibility to COVID-19. IL-6 levels were significantly correlated with disease progression (p < 0.001).

Conclusion

ACE-2 and IFITM-3 genetic variants are potential predictors of COVID-19 severity, critical outcomes, and post-COVID-19 complications. Together, these SNPs and serum IL-6 levels explain a large proportion of the variability in the severity of COVID-19 infection and its consequences among Egyptian subjects.

Polymorphisms within the SARS-CoV-2 Human Receptor Genes Associate with Variable Disease Outcomes across Ethnicities

The contribution of human genes to the variability of disease outcomes has been shown to be important across infectious diseases. Studies have shown mutations within specific human genes are associated with variable COVID-19 outcomes. We focused on the SARS-CoV-2 receptors/co-receptors to identify the role of specific polymorphisms within ACE2, TMPRSS2, NRP1 and CD147. Polymorphisms within ACE2 (rs2285666), TMPRSS2 (rs12329760), CD147 (rs8259) and NRP1 (rs10080) have been shown to associate with COVID-19 severity. Using cryopreserved samples from COVID-19-positive African, European and South Asian individuals within South Africa, we determined genotype frequencies. The genetic variant rs2285666 was associated with COVID-19 severity with an ethnic bias. African individuals with a CC genotype demonstrate more severe COVID-19 outcomes (OR = 7.5; 95% CI 1.164-80.89; p = 0.024) compared with those with a TT genotype. The expressions of ACE2 and SARS-CoV-2 viral load were measured using droplet digital PCR. Our results demonstrate rs2285666 and rs10080 were significantly associated with increased SARS-CoV-2 viral load and worse outcomes in certain ethnicities. This study demonstrates two important findings. Firstly, SARS-CoV-2 viral load is significantly lower in Africans compared with individuals of European and South Asian descent (p = 0.0002 and p < 0.0001). Secondly, SARS-CoV-2 viral load associates with specific SARS-CoV-2 receptor variants. A limited number of studies have examined the receptor/co-receptor genes within Africa. This study investigated genetic variants within the SARS-CoV-2 receptor/co-receptor genes and their association with COVID-19 severity and SARS-CoV-2 viral load across different ethnicities. We provide a genetic basis for differences in COVID-19 severity across ethnic groups in South Africa, further highlighting the importance of further investigation to determine potential therapeutic targets and to guide vaccination strategies that may prioritize specific genotypes.