ACE2 and TMPRSS2 SNPs as Determinants of Susceptibility to, and Severity of, a COVID-19 Infection

The ZNF717-rs2918520 genotype contributes to COVID-19 severity: a Taiwanese cohort study

BACKGROUND

Coronavirus disease 2019 (COVID-19) has been a challenging pandemic since late 2019 and patients with COVID-19-related severe respiratory failure associated with high mortality rates worldwide. Genetic information such as single nucleotide polymorphisms (SNPs) serves as a predictor or prognostic factor in disease development and cancer progression. This study aimed to explore the clinical associations of SNPs with mild and severe COVID-19 symptoms in the Taiwanese population.

METHODS

SARS-CoV-2-infected patients in pilot cohort study (cohort 1, n = 39) and validation cohort (cohort 2, n = 71) were enrolled. The clinical significance of SNPs in those patients with mild and severe symptoms was investigated by whole exon sequencing, polymerase chain reaction and Sanger sequencing.

RESULTS

The current study investigated Taiwanese patients with COVID-19. We found that clinical parameters such as age, aspartate aminotransferase, blood urea nitrogen, C-reactive protein, ferritin, and segment were positively associated with severe COVID-19 symptoms but that albumin, lymphocytes, and basophils correlated negatively with severe symptoms in two independent cohorts. By conducting whole-exome sequencing, we identified a novel SNP, ZNF717-rs2918520, the GG genotype of which was significantly associated with severe symptoms in COVID-19 patients.

CONCLUSIONS

Our findings highlight that the ZNF717-rs2918520 GG genotype may serve as a predictor for evaluating the severity of COVID-19 in Taiwan.

Interleukin-1 Beta rs16944 and rs1143634 and Interleukin-6 Receptor rs12083537 Single Nucleotide Polymorphisms as Potential Predictors of COVID-19 Severity

Host genetic variation has been recognized as a key predictor of diverse clinical sequelae among severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected patients. Insights into the link between the Interleukin-6 receptor (IL-6R) and Interleukin-1 beta (IL-1β) genetic variation and severe coronavirus disease 2019 (COVID-19) are crucial for developing new predictors and therapeutic targets. We aimed to investigate the association of IL-6R rs12083537, IL-1β rs16944, and IL-1β rs1143634 SNPs with the severity of COVID-19. Our study was conducted on 300 COVID-19-negative individuals (control group) and 299 COVID-19-positive cases, classified into mild, moderate, and severe subgroups. Analyses of IL-1β (rs16944, rs1143634) and IL-6R (rs12083537) SNPs' genotypes were performed using qPCR genotyping assays. The IL-1β (rs16944) CC genotype and IL-6R (rs12083537) GG genotype were substantially related to COVID-19 severity, which was also associated with comorbidities and some laboratory parameters (p < 0.001). The IL-1β (rs1143634) TT genotype was found to be protective. Likewise, the IL-1β (rs16944) CC genotype was associated with increased mortality. IL-1β rs16944 and IL-6R rs12083537 SNPs are promising potential predictors of SARS-CoV-2 disease severity. Meanwhile, the rs1143634 SNP T allele was protective against severity and mortality risk.

ACE gene polymorphism and susceptibility to hypertension in a Jordanian adult population

Hypertension is one of the most common and complicated disorders associated with genetic and environmental risk factors. The angiotensin-converting enzyme (ACE) is important in the renin-angiotensin-system pathway. The gene expression of ACE has been investigated as a possible hypertension marker. This study investigates the association between polymorphisms within the ACE1 and ACE2 genes and hypertension susceptibility in a Jordanian population. The study comprised a total of 200 hypertensive patients and 180 healthy controls. A polymerase chain reaction (PCR) was performed to genotype the candidate polymorphism (rs4646994) of the ACE1gene. The Luminex DNA array technique was used for genotyping SNPs (rs4359, rs4344, rs4341, rs4343, and rs2106809) of the ACE1 and ACE2 genes. Our findings suggest no association between SNPs and hypertension regarding allelic and genotypic frequencies. However, rs4359 was significantly associated with diet (pP = 0.049), know HTN (P = 0.042), and number of years DM (P = 0.003). rs4341 was associated with diet (P = 0.032), peripheral vascular disease (P = 0.005), and chronic kidney disease (p = 0.049). While rs4343 was associated with diet (P = 0.031), diabetes mellitus (P = 0.032), and other medication (P = 0.025). Furthermore, the haplotypes of four SNPs of the ACE1 gene showed no significant association with HTN patients and healthy controls. Our findings indicate no association between the polymorphisms in the ACE gene and the risk of hypertension development in the Jordanian adult population.

Association of ACE2 and TMPRSS2 genes variants with disease severity and most important biomarkers in COVID-19 patients in Bosnia and Herzegovina

AIM

To assess the association of single nucleotide polymorphisms (SNPs) in the ACE2 and TMPRSS2 genes with COVID-19 severity and key biomarkers.

METHODS

The study involved 750 COVID-19 patients from Bosnia and Herzegovina, divided into three groups: mild, moderate, and severe cases. Genetic variations within the ACE2 (rs2285666) and TMPRSS2 (rs2070788) genes were examined with real-time polymerase chain reaction. Biochemical markers were determined with standard procedures.

RESULTS

There was a significant difference in the rs2070788 genotype distribution between patients with mild and moderate symptoms, but not between other groups. For the rs2285666 polymorphism, no significant difference in genotype distribution was found. In patients with mild symptoms, carriers of the GG genotype of rs2070788 had significantly higher total bilirubin levels than carriers of the AA genotype. Similarly, carriers of the TT genotype of rs2285666 had significantly higher activated partial thromboplastin time and international normalized ratio, and lower lactate dehydrogenase levels compared with the CC genotype. Among patients with severe symptoms, carriers of the GG genotype showed significantly higher potassium levels than carriers of the AA genotype, while carriers of the TT genotype showed significantly higher erythrocyte count as well as hemoglobin and hematocrit levels compared with the CC genotype.

CONCLUSION

This study highlights the role of genetic factors, particularly SNPs in the ACE2 and TMPRSS2 genes, in determining COVID-19 severity, aiding patient risk assessment and prognosis.

Association of specific ACE2 and TMPRSS2 variants with circulatory cytokines of COVID-19 Emirati patients

INTRODUCTION

The COVID-19 pandemic represented one of the most significant challenges to researchers and healthcare providers. Several factors determine the disease severity, whereas none alone can explain the tremendous variability. The Single nucleotide variants (SNVs) in angiotensin-converting enzyme-2 (ACE2) and transmembrane serine protease type-2 (TMPRSS2) genes affect the virus entry and are considered possible risk factors for COVID-19.

METHODS

We compiled a panel of gene variants from both genes and used in-silico analysis to predict their significance. We performed biological validation to assess their capacity to alter the ACE2 interaction with the virus spike protein. Subsequently, we conducted a retrospective comparative genome analysis on those variants in the Emirati patients with different disease severity (total of 96) along with 69 healthy control subjects.

RESULTS

Our results showed that the Emirati population lacks the variants that were previously reported as associated with disease severity, whereas a new variant in ACE2 "Chr X:g.15584534" was associated with disease severity specifically among female patients. In-silico analysis revealed that the new variant can determine the ACE2 gene transcription. Several cytokines (GM-CSF and IL-6) and chemokines (MCP-1/CCL2, IL-8/CXCL8, and IP-10/CXCL10) were markedly increased in COVID-19 patients with a significant correlation with disease severity. The newly reported genetic variant of ACE2 showed a positive correlation with CD40L, IL-1β, IL-2, IL-15, and IL-17A in COVID-19 patients.

CONCLUSION

Whereas COVID-19 represents now a past pandemic, our study underscores the importance of genetic factors specific to a population, which can influence both the susceptibility to viral infections and the level of severity; subsequently expected required preparedness in different areas of the world.

Genetic association of ACE2 and TMPRSS2 polymorphisms with COVID-19 severity; a single centre study from Egypt

BACKGROUND

Since the emergence of the COVID-19 infection in China, it has caused considerable morbidity, mortality, and economic burden. It causes the vast majority of clinical manifestations, ranging from mild or even no symptoms to severe respiratory failure. There are many risk factors for severe COVID-19, such as old age, male gender, and associated comorbidities. A major role for genetic factors may exist. The SARS-CoV-2 virus enters the cell primarily through ACE2 receptors. rs2285666 is one of many polymorphisms found in the ACE2 receptor gene. To enable endosome-independent entry into target cells, the transmembrane protease serine-type 2 (TMPRSS2) is necessary to cleave the virus' spike (S) glycoprotein. TMPRSS2 is characterized by an androgen receptor element. The rs12329760 polymorphism in TMPRSS2 may explain different genetic susceptibilities to COVID-19.

METHOD

This cross-sectional study was held in Mansoura University Hospitals during the period from June 2020 to April 2022 on patients who had mild and severe COVID-19. Demographic, clinical, and laboratory data were collected, and the TaqMan real-time polymerase chain was used for allelic discrimination in the genotyping of rs2285666 and rs12329760.

RESULTS

This study included 317 Egyptian patients, aged from 0.2 to 87 years. Males were 146, while females were 171. They were divided into mild and severe groups (91 and 226 patients, respectively) based on their clinical symptoms. There was a significant association between COVID-19 severity and male gender, hypertension, diabetes mellitus, and high CRP. The genotype and allele frequency distributions of the ACE2 rs2285666 polymorphism showed no significant association with the severity of COVID-19 in both. In contrast, in TMPRSS2 rs12329760 minor T allele and CT, TT genotypes were significantly associated with a reduced likelihood of developing severe COVID-19.

CONCLUSION

Our study indicates that the ACE2 rs2285666 polymorphism is not related to the severity of COVID-19, whether genotypes or alleles. In TMPRSS2 rs12329760, the dominant model and T allele showed significantly lower frequencies in severe cases, with a protective effect against severity. The discrepancies with previous results may be due to variations in other ACE2 receptor-related genes, inflammatory mediators, and coagulation indicators. Haplotype blocks and differences in racial makeup must be taken into consideration. Future research should be done to clarify how ethnicity affects these polymorphisms and how other comorbidities combine to have an additive effect.

Evaluation of relationship between TMPRSS2 p.(Val197Met) variant and COVID-19 susceptibility and severity

BACKGROUND

The World Health Organization (WHO) declared Coronavirus Disease 2019 (COVID-19) a global pandemic on March 11, 2020. Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection has killed millions of people and had a terrible effect on society. The transmembrane protease serine 2 (TMPRSS2) enzyme is essential in the initial phases of the interplay between the SARSCoV-2 and the host cells by assisting viral entrance.

METHODS

This observational case-control study involved 150 participants, 100 adult patients with COVID-19, 50 of whom appeared healthy and had no history of or symptoms of COVID-19 infection when the study was conducted. Between January and April 2022, patients were taken as inpatients in isolation units or through recruitment from the COVID-19 clinic at Kasr Al-Ainy Cairo University Hospitals. According to the National Institutes of Health guidelines (2021), they were categorised into three categories: mild, moderate, and severe. TMPRSS2 p.(Val197Met) variant genotyping was evaluated using TaqMan Real-Time PCR.

RESULTS

The study showed a substantial difference between the mild and severe COVID-19 patient groups regarding their TMPRSS2 (p.Val197Met) genotypes (P value = 0.046). The C allele was significantly more prevalent in the mild, moderate and severe COVID-19 patient categories (77.8%, 89.7% and 91.7%, respectively) and the control group (80%). Meanwhile, the T allele was more prevalent in the mild (22.2%) and control (20%) groups. There was a statistically significant difference in allelic distribution between the mild and severe groups (P value = 0.034).

CONCLUSION

The study showed a connection between the TMPRSS2 gene variant p.(Val197Met) and the degree of illness. We concluded that the T(mutant) allele was protective against severe COVID-19 because it was linked to lesser disease severity.

Association of genetic polymorphisms with COVID-19 infection and outcomes: An updated meta-analysis based on 62 studies

Background

The relationship between genetic polymorphisms and coronavirus disease 2019 (COVID-19) remains to be inconsistent. This meta-analysis aimed to provide an updated evaluation of the role of genetic polymorphisms in the infection, severity and mortality of COVID-19 based on all available published studies.

Methods

A systematic search was performed using six databases: PubMed, Embase, Web of Science, Cochrane Library, Chinese National Knowledge Infrastructure (CNKI) and Wanfang. Summary odds ratios (ORs) and corresponding 95 % confidence intervals (CIs) were used to calculate the genotypic comparison. All statistical analyses were conducted in Stata 12.0.

Results

A total of 62 studies with 19600 cases and 28899 controls was included in this meta-analysis. For COVID-19 infection, ACE Ins/Del polymorphism might be related with significantly decreased risk of COVID-19 infection under dominant, homozygote and allelic models. Meanwhile, the IFITM3 rs12252 and TMPRSS2 rs12329760 polymorphisms were significantly associated with the increased risk of COVID-19 infection under one or more models. Regarding COVID-19 severity, ACE2 rs2074192, ACE2 rs2106809, IFITM3 rs12252 and VDR rs1544410 polymorphisms might be related with significantly increased risk of COVID-19 severity in one or more models. Moreover, the analysis of TMPRSS2 rs2070788 indicated that a variant A allele decreased the risk of COVID-19 severity in recessive model. For COVID-19 mortality, the variant C allele of IFITM3 rs12252 polymorphism might be related with significantly increased risk of COVID-19 mortality under all genetic models.

Conclusions

This meta-analysis indicated that he infection, severity or mortality of COVID-19 were related to the above genetic polymorphisms, which might provide an important theoretical basis for understanding the clinical feature of COVID-19 disease.

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.

From cardiovascular system to brain, the potential protective role of Mas Receptors in COVID-19 infection

Coronavirus disease 2019 (COVID-19) has been declared a new pandemic in March 2020. Although most patients are asymptomatic, those with underlying cardiovascular comorbidities may develop a more severe systemic infection which is often associated with fatal pneumonia. Nonetheless, neurological and cardiovascular manifestations could be present even without respiratory symptoms. To date, no COVID-19-specific drugs are able for preventing or treating the infection and generally, the symptoms are relieved with general anti-inflammatory drugs. Angiotensin-converting-enzyme 2 (ACE2) may function as the receptor for virus entry within the cells favoring the progression of infection in the organism. On the other hand, ACE2 is a relevant enzyme in renin angiotensin system (RAS) cascade fostering Ang1-7/Mas receptor activation which promotes protective effects in neurological and cardiovascular systems. It is known that RAS is composed by two functional countervailing axes the ACE/AngII/AT1 receptor and the ACE/AngII/AT2 receptor which counteracts the actions mediated by AngII/AT1 receptor by inducing anti-inflammatory, antioxidant and anti-growth functions. Subsequently an "alternative" ACE2/Ang1-7/Mas receptor axis has been described with functions similar to the latter protective arm. Here, we discuss the neurological and cardiovascular effects of COVID-19 highlighting the role of the stimulation of the RAS "alternative" protective arm in attenuating pulmonary, cerebral and cardiovascular damages. In conclusion, only two clinical trials are running for Mas receptor agonists but few other molecules are in preclinical phase and if successful these drugs might represent a successful strategy for the treatment of the acute phase of COVID-19 infection.

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.

A comprehensive review of ACE2, ACE1, TMPRSS2 and IFITM3 gene polymorphisms and their effect on the severity of COVID-19

Recent events have raised concerns about the outbreak of a pandemic by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). An infection caused by a virus can provoke an inflammatory reaction, which can result in severe lung damage, failure of several organs, and death. The unique genetic makeup of each individual may be a component in the development of each of these responses. In this context, genetic variants of the genes linked to the invasion of the virus into the host's body can be analyzed. Various elements have a function in viral entry. ACE2 is used by SARS-CoV-2 as a receptor to enter the cell. TMPRSS2 is then responsible for cutting the virus into its components. In addition, lung damage occurs when there is an imbalance between ACE1 and ACE2. Another component that plays a significant role in virus penetration is called IFITM3, which is created as a reaction to interferon. This protein prevents viruses in the Coronaviridae family from entering cells. This study aimed to analyze DNA polymorphisms in the ACE2, ACE1, TMPRSS2, and IFITM3 genes. Findings showed certain polymorphisms appear to be associated with the severity of the disease, including respiratory, coronary, and neurological disorders. The results also indicated that certain polymorphisms were protective against this virus. Varying populations have a different frequency of high-risk polymorphisms, so different treatment and preventative techniques must be implemented. Additional population studies should be conducted in this region to reduce the incidence of COVID-19-related morbidity and mortality.

Genetic Variants within SARS-CoV-2 Human Receptor Genes May Contribute to Variable Disease Outcomes in Different Ethnicities

The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has evolved into a global pandemic, with an alarming infectivity and mortality rate. Studies have examined genetic effects on SARS-CoV-2 disease susceptibility and severity within Eurasian populations. These studies identified contrasting effects on the severity of disease between African populations. Genetic factors can explain some of the diversity observed within SARS-CoV-2 disease susceptibility and severity. Single nucleotide polymorphisms (SNPs) within the SARS-CoV-2 receptor genes have demonstrated detrimental and protective effects across ethnic groups. For example, the TT genotype of rs2285666 (Angiotensin-converting enzyme 2 (ACE2)) is associated with the severity of SARS-CoV-2 disease, which is found at higher frequency within Asian individuals compared to African and European individuals. In this study, we examined four SARS-CoV-2 receptors, ACE2, Transmembrane serine protease 2 (TMPRSS2), Neuropilin-1 (NRP1), and Basigin (CD147). A total of 42 SNPs located within the four receptors were reviewed: ACE2 (12), TMPRSS2 (10), BSG (CD147) (5), and NRP1 (15). These SNPs may be determining factors for the decreased disease severity observed within African individuals. Furthermore, we highlight the absence of genetic studies within the African population and emphasize the importance of further research. This review provides a comprehensive summary of specific variants within the SARS-CoV-2 receptor genes, which can offer a better understanding of the pathology of the SARS-CoV-2 pandemic and identify novel potential therapeutic targets.

TYK2 single-nucleotide variants associated with the severity of COVID-19 disease

Coronavirus disease 2019 (COVID-19) is a lethal disease caused by the coronavirus SARS-CoV-2, which can result in a broad clinical spectrum of respiratory symptoms. While many clinical risk factors such as concomitant chronic diseases play roles in the pathophysiology of COVID-19, genetic predisposition factors have not been widely studied. The aim of this study was, therefore, to evaluate the relationship between some singlenucleotide polymorphisms (SNPs) of the human genes TYK2 and ACE2 and the severity of SARS-CoV-2 infection. Genomic DNA was isolated from 200 SARS-CoV-2-infected individuals with severe (n = 100) or mild (n = 100) disease. Owing to the importance of ACE2 and TYK2 genes in regulating the immune response to SARS-CoV-2 infection, TYK2 gene SNPs, i.e. rs2304255, rs2304256, rs12720270, and rs12720354 and ACE2 rs382746 variants, were genotyped in the samples. To confirm the results, the expression of different TYK2 genotypes was investigated using real-time PCR. The presence of the nucleotide T at the locus rs2304255 was shown to be a risk factor linked to disease severity (OR [95% CI] = 3.2485 [2.1554-4.8961]). Similarly, the presence of A at the locus rs12720354 increased the risk of severity (OR [95% CI]) = 3.9721 [2.6075-6.0509]). In contrast, the presence of A at the loci rs2304256 and rs12720270 was observed to reduce the severity risk (OR [95% CI] = 0.2495 [0.1642-0.3793] and 0.1668 [0.1083-0.2569], respectively). Real-time PCR results also demonstrated that the expression level of TYK2 in samples with the TT genotype of rs2304255 and the AA genotype of rs12720354 and in samples with the GG genotype of rs12720207 was significantly lower than in those with other genotypes. The results of this study suggest that TYK2 SNPs might be utilized to identify individuals who are at risk for severe COVID-19, in order to better manage their health care. It is predicted that the presence of some alleles (T in rs2304255, A in rs12720354, and G in rs12720207) of TYK2 can affect COVID-19 severity by reducing TYK2 expression and thereby affecting the regulatory role of TYK2 in the immune response.

TMPRSS2 polymorphism (rs12329760) and the severity of the COVID-19 in Iranian population

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has been responsible for the recent pandemic since early 2020. Due to the wide range of clinical symptoms of this disease, from asymptomatic to severe and critical forms, it seems that genetic differences among patients, along with other factors (such as gender, age, and underlying diseases), can explain part of the variation in disease symptoms. The TMPRSS2 enzyme plays a vital role in the early stages of the interaction of the SARS-CoV-2 with the host cells by facilitating viral entry. There is a polymorphism in the TMPRSS2 gene, called rs12329760(C to T) as a missense variant, which causes the replacement of valine to methionine in the TMPRSS2 protein at position 160. The present study investigated the association between the TMPRSS2 genotype and the severity of the Coronavirus disease 2019 (COVID-19) in Iranian patients. The TMPRSS2 genotype of 251 COVID-19 patients (151 patients with asymptomatic to mild and 100 patients with severe to critical symptoms) was detected on genomic DNA extracted from patients' peripheral blood via the ARMS-PCR method. Our results showed a significant association between the minor T allele and the severity of the COVID-19 (P-value = 0.043) under the dominant and additive inheritance model. In conclusion, the results of this study showed that the T allele of the rs12329760 in the TMPRSS2 gene is a risk allele for severe form of COVID-19 in Iranian patients in contrast to most previous studies on this variant in European ancestry populations which suggested this variant as a protective allele. Our results reiterate to the ethnic-specific risk alleles and hidden unknown complexity behind the host genetic susceptibility. However, further studies are needed to address the complex mechanisms behind the interaction of the TMPRSS2 protein and the SARS-CoV-2 and the role of rs12329760 polymorphism in determining the disease severity.

Relevance of HLA-DP/DQ and INF-λ4 Polymorphisms to COVID-19 Outcomes

Background: Single nucleotide polymorphisms provide information on individuals' potential reactions to environmental factors, infections, diseases, as well as various therapies. A study on SNPs that influence SARS-CoV-2 susceptibility and severity may provide a predictive tool for COVID-19 outcomes and improve the customized coronavirus treatment. Aim: To evaluate the role of human leukocyte antigens DP/DQ and IFNλ4 polymorphisms on COVID-19 outcomes among Egyptian patients. Participants and Methods: The study involved 80 patients with severe COVID-19, 80 patients with mild COVID-19, and 80 non-infected healthy volunteers. Genotyping and allelic discrimination of HLA-DPrs3077 (G/A), HLA-DQrs7453920 (A/G), and IFNλ4 rs73555604 (C/T) SNPs were performed using real-time PCR. Results: Ages were 47.9 ± 8, 44.1 ± 12.1, and 45.8 ± 10 years in severe, mild and non-infected persons. There was a statistically significant association between severe COVID-19 and male gender (p = 0.002). A statistically significant increase in the frequency of HLA-DPrs3077G, HLA-DQrs7453920A, and IFNλ4rs73555604C alleles among severe COVID-19 patients when compared with other groups (p < 0.001). Coexistence of these alleles in the same individual increases the susceptibility to severe COVID-19 by many folds (p < 0.001). Univariate and multivariate logistic regression analysis for the studied parameters showed that old age, male gender, non-vaccination, HLA-DQ rs7453920AG+AA, HLA-DPrs3077GA+GG, and IFNλ4rs73555604CT+CC genotypes are independent risk factors for severe COVID-19 among Egyptian patients. Conclusion: HLA-DQ rs7453920A, HLA-DPrs3077G, and IFNλ4rs73555604C alleles could be used as markers of COVID-19 severity.

Impact of ACE and Endoplasmic Reticulum Aminopeptidases Polymorphisms on COVID-19 Outcome

Background: COVID-19 outcomes display multiple unexpected varieties, ranging from unnoticed symptomless infection to death, without any previous alarm or known aggravating factors. Aim: To appraise the impact of ACErs4291(A/T) and ERAP1rs26618(T/C) human polymorphisms on the outcome of COVID-19. Subjects and methods: In total, 240 individuals were enrolled in the study (80 with severe manifestations, 80 with mild manifestations, and 80 healthy persons). ACErs4291(A/T) and ERAP1rs26618(T/C) genotyping was performed using RT-PCR. Results: The frequency of the ACErs4291AA genotype was higher among the severe COVID-19 group than others (p < 0.001). The ERAP1rs26618TT genotype frequency was higher among the severe COVID-19 group in comparison with the mild group (p < 0.001) and non-infected controls (p = 0.0006). The frequency of the ACErs4291A allele was higher among severe COVID-19 than mild and non-infected groups (64.4% vs. 37.5%, and 34.4%, respectively), and the ERAP1rs26618T allele was also higher in the severe group (67.5% vs. 39.4%, and 49.4%). There was a statistically significant association between severe COVID-19 and ACErs4291A or ERAP1rs26618T alleles. The coexistence of ACErs4291A and ERAP1rs26618T alleles in the same individual increase the severity of the COVID-19 risk by seven times [OR (95%CI) (LL−UL) = 7.058 (3.752−13.277), p < 0.001). A logistic regression analysis revealed that age, male gender, non-vaccination, ACErs4291A, and ERAP1rs26618T alleles are independent risk factors for severe COVID-19. Conclusions: Persons carrying ACErs4291A and/or ERAP1rs26618T alleles are at higher risk of developing severe COVID-19.

Polymorphisms in ACE1, TMPRSS2, IFIH1, IFNAR2, and TYK2 Genes Are Associated with Worse Clinical Outcomes in COVID-19

Although advanced age, male sex, and some comorbidities impact the clinical course of COVID-19, these factors only partially explain the inter-individual variability in disease severity. Some studies have shown that genetic polymorphisms contribute to COVID-19 severity; however, the results are inconclusive. Thus, we investigated the association between polymorphisms in ACE1, ACE2, DPP9, IFIH1, IFNAR2, IFNL4, TLR3, TMPRSS2, and TYK2 and the clinical course of COVID-19. A total of 694 patients with COVID-19 were categorized as: (1) ward inpatients (moderate symptoms) or patients admitted at the intensive care unit (ICU; severe symptoms); and (2) survivors or non-survivors. In females, the rs1990760/IFIH1 T/T genotype was associated with risk of ICU admission and death. Moreover, the rs1799752/ACE1 Ins and rs12329760/TMPRSS2 T alleles were associated with risk of ICU admission. In non-white patients, the rs2236757/IFNAR2 A/A genotype was associated with risk of ICU admission, while the rs1799752/ACE1 Ins/Ins genotype, rs2236757/IFNAR2 A/A genotype, and rs12329760/TMPRSS2 T allele were associated with risk of death. Moreover, some of the analyzed polymorphisms interact in the risk of worse COVID-19 outcomes. In conclusion, this study shows an association of rs1799752/ACE1, rs1990760/IFIH1, rs2236757/IFNAR2, rs12329760/TMPRSS2, and rs2304256/TYK2 polymorphisms with worse COVID-19 outcomes, especially among female and non-white patients.

SARS-CoV-2 Infection and Candidate Biomarkers

Severe acute respiratory syndrome coronavirus 2 is a virus that can still infect individuals and whose deadly effects continue despite the current vaccines and drugs. Since 2019, many studies on the pathogenesis of the disease have been completed and continue to be done. In addition to the diagnosis and treatment of the disease, many molecules that can be markers of the disease have been investigated. In the early stages of the pandemic, many nonspecific and infection-related laboratory findings and chest computed tomography were used to obtain information about the diagnosis of the disease. The more individual molecules became associated with the disease yet. The purpose of this review is to summarize the impact and role of many molecules associated with coronavirus disease-2019 infection that have been previously used and newly revealed. Numerous studies are summarized in this review. The obtained data show that previously used laboratory findings and new potential biomarkers are not specific to the disease. New potential biomarkers have been associated with the severity of the disease itself, as can be seen with lung imaging and even with routine laboratory findings. One of the important points that are seen frequently in studies is that the effectiveness of these molecules has been shown not only in coronavirus disease-2019 infection but also in many other diseases. This removes the pathogenesis of the disease from being a unique mechanism created by the Severe acute respiratory syndrome coronavirus 2 and provides a general perspective formed by viral or bacterial infections. However, there are still many molecular changes that need to be investigated. Future studies will continue to update themselves with the mutations of the virus.

A Polymorphism in the TMPRSS2 Gene Increases the Risk of Death in Older Patients Hospitalized with COVID-19

BACKGROUND

Transmembrane serine protease type 2 (TMPRSS2) and angiotensin-converting enzyme 2 (ACE2) are the main molecules involved in the entry of SARS-CoV-2 into host cells. Changes in TMPRSS2 expression levels caused by single nucleotide polymorphisms (SNPs) may contribute to the outcome of COVID-19. The aim was to investigate the association between TMPRSS2 gene polymorphisms and the risk of death in hospitalized patients with COVID-19.

METHODS

We included patients with confirmed COVID-19, recruited from two hospitals in northeastern Brazil from August 2020 to July 2021. Two functional polymorphisms (rs2070788 and rs12329760) in TMPRSS2 were evaluated by real-time PCR. The Kaplan-Meier method was used to estimate death. The Cox's proportional hazards model was used to adjust for potentially confounding factors.

RESULTS

A total of 402 patients were followed prospectively. Survival analysis demonstrated that older patients carrying the rs2070788 GG genotype had shorter survival times when compared to those with AG or AA genotypes (p = 0.009). In multivariable analysis, the GG genotype was a factor independently associated with the risk of death in older individuals (hazard ratio = 4.03, 95% confidence interval 1.49 to 10.84).

CONCLUSIONS

The rs2070788 polymorphism in TMPRSS2 increases risk of death four-fold in older patients hospitalized with COVID-19.

Angiotensin-converting enzyme 2 rs2285666 polymorphism and clinical parameters as the determinants of COVID-19 severity in Iranian population

Host genetic factors may be correlated with the severity of coronavirus disease 2019 (COVID-19). Angiotensin-converting enzyme 2 (ACE2) plays a vital role in viral cell entrance. The current study aimed to evaluate the association of ACE2 rs2285666 polymorphism and clinical parameters with COVID-19 mortality. The ACE2 rs2285666 polymorphism was genotyped using the polymerase chain reaction-restriction fragment length polymorphism in 556 recovered and 522 dead patients. In this study, the frequency of ACE2 rs2285666 CC was significantly higher than TT genotype in dead patients. The multivariate logistic regression analysis results showed that the higher levels of alanine aminotransferase, alkaline phosphatase, creatinine, erythrocyte sedimentation rate, and C-reactive protein and the low levels of uric acid, cholesterol, low density lipoprotein, 25-hydroxyvitamin D, real-time PCR Ct values, and ACE2 rs2285666 CC genotype were associated with increased mortality rates after COVID-19. In conclusion, our findings demonstrated a possible link between COVID-19 mortality, clinical parameters, and ACE2 rs2285666 CC. Further research is required to confirm these results.

Global distribution of ACE1 (rs4646994) and ACE2 (rs2285666) polymorphisms associated with COVID-19: A systematic review and meta-analysis

BACKGROUND

Recent studies emphasize the significant impact of the renin-angiotensin aldosterone system (RAAS) as a risk factor associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. However, according to the literature, the effect of rs4646994 and rs2285666 polymorphisms on susceptibility and progression to severe clinical outcomes is still controversial. Our aim was to investigate the effect of polymorphisms such as rs4646994 and rs2285666 on susceptibility to coronavirus disease-2019 (COVID-19).

METHODS

We conducted a comprehensive literature search using databases such as ISI Web of Science, PubMed, Scopus, and Google Scholar to retrieve studies on the effect of two polymorphisms (rs4646994 and rs2285666) of the angiotensin-converting enzyme (ACE) gene on COVID-19. Finally, the effect of each polymorphism on SARS-CoV-2 infection was measured based on the odds ratio with 95% confidence intervals.

RESULTS

Analysis of the rs4646994 polymorphism showed that the frequency of the D allele in patients infected with COVID-19 was higher than that the I allele. Moreover, the authors found that the DD genotype increased the risk of severe disease by 1.7-fold in Asian population, whereas, this was not the case in the Western population. However, the rs4646994 II genotype plays a protective role against COVID-19 in Western countries. In the case of the rs2285666 polymorphism based on patient ethnicity, the C allele had the highest frequency. Interestingly, in people harboring the GG and TT genotypes, the risk of progression to severe disease significantly increased, while people with genotypes such as GA, AA and CC seem to be more resistant to severe Covid-19.

CONCLUSIONS

Based on geographical region, the rs4646994 DD genotype may be considered as a predictive biomarker to identify the susceptibility of human to SARS-CoV-2 infection and severe COVID-19 outcomes. We also concluded that individuals with GG and TT genotypes are significantly more susceptible to severe outcomes of disease, while conversely, individuals with GA, AA, and CC genotypes are less susceptible to severe COVID-19.

Association between single nucleotide polymorphism of human angiotensin-converting enzyme 2 gene locus and clinical severity of COVID-19

Background

Coronavirus disease 2019 (COVID-19) is a devastating pandemic-causing disease with a variable severity among populations. Genetic studies have pinpointed angiotensin-converting enzyme 2 (ACE2), a key enzyme for viral entry, for its possible linkage to the disease progression. The present study aimed to investigate the potential association between single nucleotide polymorphisms (SNPs) of human ACE2 gene with the severity and outcomes of COVID-19 for better patient management.

Methods

In this observational cross-sectional study, COVID-19 confirmed patients were classified into moderate and severe cases according to the "Ain Shams University Hospitals Pocket Guide for COVID-19 Diagnosis." Genetic analysis of ACE2 SNP rs2048683 was carried out using a TaqMan assay with the real-time polymerase chain reaction (PCR) technique.

Results

Among 90 confirmed COVID-19 patients, 78.9% (71/90) were classified as severe, and 21.1% (19/90) were classified as moderate. Laboratory biomarkers were significantly (P = 0.000) higher in the severe group than in the moderate group. Similarly, associated comorbidities such as hypertension were significant (P = 0.000) in the severe group, whereas asthma and deep venous thrombosis were significant in the moderate group (P = 0.007 and 0.006, respectively). Elevated serum ferritin level (odds ratio (OR) 162.589, 95% confidence interval (CI) 8.108-3260.293) and ACE2 rs2048683 genotype GG/G (OR 5.852, 95% CI 1.586-21.591) were both considered independent risk factors for severe disease.

Conclusion

The findings of the present study provide preliminary evidence of an association between ACE2 rs2048683 SNPs and COVID-19 severity in the Egyptian population, which may inform the need for targeted management.

Supplementary Information

The online version contains supplementary material available at 10.1186/s43042-022-00331-8.