Single nucleotide polymorphisms located in TNFA, IL1RN, IL6R, and IL6 genes are associated with COVID-19 risk and severity in an Iranian population

Determination of both the expression and serum levels of epidermal growth factor and transforming growth factor β1 genes in COVID-19

We aimed to evaluate the effects of both the expression and serum levels of Epidermal growth factor (EGF) and Transforming growth factor-β1 (TGF-β1) genes in patients with different degrees of cellular damage as mild, moderate, severe, and critical illness that can lead to fibrosis caused by SARS-CoV-2. Totally 45 individuals (male: 21(46.67%); female: 24(53.33%)) with COVID-19 infection were included in this study. Four groups were constituted as mild (n = 16)], moderate (n = 10), severe (n = 10), and critical (n = 9) according to the severity of the disease. Blood samples were drawn from the patients, and all of the hemograms, EGF and TGFβ1 gene expression, and serum levels were evaluated. The mean age of individuals was 57.311 ± 18.383 (min: 28, max: 94). Significant differences were found among the groups for PLT (χ2 = 9.955; p = 0.019), CRP (χ2 = 7.693; p = 0.053), Ferritin (χ2 = 22.196; p < 0.001), D-dimer (χ2 = 21.982; p = 0.000), LDH (χ2 = 21.807; p < 0.001) and all these parameters (exclude PLT in severe groups) was increased depending on the severity of the disease. Additionally, significant differences were detected for EGF (χ2 = 29.528; p < 0.001), TGFB1 (χ2 = 28.981; p < 0.001) expression (that increased depending on the disease severity), and EGF (χ2 = 7.84; p = 0.049), TGFB1 (χ2 = 17.451; p = 0.001) serum concentration levels (that decreased depending on the disease severity). This study found statistically significant differences for both EGF 2-ΔΔCt. TGFβ1 2-ΔΔCt and EGF, TGFβ1 serum concentration values among all patient groups. As disease severity increased, EGF 2-ΔΔCt. TGFβ1 2-ΔΔCt levels increased, while EGF and TGFβ1 serum concentration levels decreased. Perhaps this study will be useful in managing COVID-19 infection severity and pulmonary fibrosis cases secondary to COVID-19.

High nasopharyngeal and serum IL-6 levels and the - 573G > C polymorphism (rs1800796) are linked with the risk of severe COVID-19 in a Mexican population: a case‒control study

BACKGROUND

COVID-19 was the leading cause of death in Mexico between 2020 and 2021. SARS-CoV-2 infection varies widely among individuals and populations. Since variations in genes related to the immune response may play a role in the susceptibility to and outcome of COVID-19, the associations of gene polymorphisms (SNPs) of IL-6 (- 573G > C, rs1800796), TNF-α (- 308G > A, rs1800629), and IFN-γ (- 1615 C > T, rs2069705) with the expression levels of these proteins in the nasopharynx and serum were evaluated in a Mexican population with mild, severe, or critical COVID-19.

METHODS

A total of 560 COVID-19 patients (309 mild, 163 severe, and 88 critical cases) and 560 age- and sex-matched COVID-19-negative controls were recruited for this case‒control study. The selected SNPs were genotyped via allelic discrimination. Logistic regression analysis was conducted considering four models of inheritance, and ORs were determined for each genotypic variant, adjusting for associated comorbidities in the multivariate model. The nasopharyngeal mRNA expression levels of IL-6, IFN-γ and TNF-α were determined. The levels of IL-6, IFN-γ, IFN-α2, and TNF-α in the serum were quantified. Significant differences were assessed via the Wilcoxon Mann‒Whitney U test.

RESULTS

The C allele of the IL-6 - 573 SNP was associated with a greater risk of mild and severe COVID-19 (OR: 2.3, CI: 1.897-2.838, p = 0.0001; and OR: 1.5, CI: 1.167-1.949, p = 0.002, respectively), whereas the A allele of the TNF-α - 308 SNP and the T allele of the IFN-γ - 1615 SNP were shown protective roles against severe COVID-19 (OR: 0.3, CI: 0.189-0.537, p = 0.0001; and OR: 0.7, CI: 0.563-1.006, p = 0.05) and against critical COVID-19 (OR: 0.3, CI: 0.158-0.640, p = 0.001; and OR: 0.4, CI: 0.290-0.678, p = 0.0001), adjusting for diabetes and hypertension. Nasopharyngeal IL-6 expression levels were lower in mild COVID-19 patients (p = 0.001) than in critical patients (p = 0.005). Serum IL-6 levels were significantly elevated in the critical cases (p = 0.01).

CONCLUSIONS

Our results revealed that the IL-6 - 573 G > C SNP and increased IL-6 nasopharyngeal and serum levels are associated with the risk of severe COVID-19 in a Mexican population.

Upregulation of the MAP2K4 gene triggers endothelial-mesenchymal transition in COVID-19

BACKGROUND

SARS-CoV-2 infection is marked by an excessive inflammatory response, leading to elevated production of pro-inflammatory cytokines through activation of intracellular pathways like mitogen-activated protein kinase (MAPK). Viruses can use the MAPK signaling pathway to their advantage, but the relationship of this pathway to the severe SARS-CoV-2 period has not been fully elucidated. MAP2K4 is involved in the MAPK signaling pathway and affects cellular processes such as cell-cell junction, cell proliferation, differentiation and apoptosis.

METHODS AND RESULTS

In this study, we sought to determine the associated biomarkers that are involved in the MAP2K4 pathway and elucidate its possible roles in terms of some clinical features associated with COVID-19. We evaluated the expressions of MAP2K4, SNAI1, SLUG, ZEB1 and E-Cadherin. For this purpose, we prospectively recruited 66 individuals, 39 of whom were women and had a mean age of 65 years. The results revealed that MAP2K4 upregulation increased SNAI1 gene expression level whereas E- Cadherin level was decreased in SARS-CoV-2 positive participants. In addition, negative correlations were determined with PLT, Lymphocyte and CKMB and E- Cadherin levels in positive participants. We also observed a negative correlation between the MAP2K4 and AST, and a positive correlation between SLUG and BUN, ZEB1 and CK.

CONCLUSIONS

We conclude that SARS-CoV-2 infection triggers fibrosis by increasing MAP2K4 regulation. Additionally, this is the first study to demonstrate the possible contribution of MAP2K4 in influencing COVID-19 clinical features, which may be relevant for identifying COVID-19 positive participants with severe complications.

Humoral Immunity Profiling to Pandemic and Bat-Derived Coronavirus Variants: A Geographical Comparison

Dynamic pathogen exposure may impact the immunological response to SARS-CoV-2 (SCV2). One potential explanation for the lack of severe SCV2-related morbidity and mortality in Southeast Asia is prior exposure to related betacoronaviruses. Recent discoveries of SCV2-related betacoronaviruses from horseshoe bats (Rhinolophus sinicus) in Thailand, Laos, and Cambodia suggest the potential for bat-to-human spillover exposures in the region. In this work, serum antibodies to protein constructs from SCV2 and a representative bat coronavirus isolated in Cambodia (RshSTT182) are measured in pre-pandemic Cambodian human sera using ELISA assays. Of 293 Cambodian samples tested (N = 131 with acute malaria, n = 162 with acute undifferentiated febrile illness), 32 (10.9%) are seropositive for SCV2 based on established Spike and receptor-binding domain (RBD) cutoffs. Within SCV2 seropositive samples, 16 (50%) have higher antibody levels to antigens from the representative virus RshSTT182 versus SCV2 antigens; competitive binding ELISA assays demonstrate inhibition of reactivity to SCV2 Spike after pre-incubation with RshSTT182 Spike. Surrogate virus neutralization tests demonstrate that 8/30 (26.7%) SCV2 ELISA positive pre-pandemic Cambodian samples have neutralizing activity against SCV2, while 14/30 (46.7%) have activity against other SCV2-related betacoronaviruses. These data suggest that exposure to related betacoronaviruses may elicit cross-reactive immunity to SCV2 prior to the global pandemic.

Study of TNF-α, IFN-γ, IL-10, TGF-β and IL-6 Gene Polymorphisms in a Cohort of Professionals Who Worked in the First Pandemic Wave in the Brazilian Amazon

Genetic polymorphisms in genes that enable the production of an effective host immune response, such as single nucleotide polymorphisms (SNPS) in the IL-6, INF-alpha, IFN-gamma, IL-10, TGF-beta genes can cause unfavorable clinical conditions or susceptibility to pathologies. The objective of this work is to evaluate the epidemiological and genetic profile of professionals from health institutions during the first pandemic wave. A case-control study was performed with convenience sampling from health institutions (HI) workers from Belém-PA, Northern Brazil (N = 213), divided into symptomatology groups (Asymptomatic-AS, n = 91; and Symptomatic-SI, n = 122); and severity groups classified by chest computerized tomography-CCT data (symptomatic with pulmonary involvement-SCP, n = 37; symptomatic without pulmonary involvement-SSP, n = 8). Genotyping was performed by sanger sequencing for SNP TNF-α -308 G/A (rs1800629), IFN-γ +874 T/A (rs2430561), TGF-β codon 10 (rs1982073), codon 25 (rs1800471), IL-6 - 174 G/C (rs180079), IL-10 - 1082 A/T (rs1800896), -819 C/T (rs1800871), and -592 A/C (rs1800872), and statistical analysis through the Epilfo program. Significant association was observed between the presence of comorbidities and poor prognosis of COVID-19 (especially between COVID-19 and overweight and obesity). Only the TNF-α 308 G/A snp was significantly associated with the symptoms and severity of COVID-19. These findings about this TNF-α SNP passed in the multiple testing correction at a false discovery rate (FDR)< 0.05. These data can help medicine and the scientific community understand the influence of genetics and epidemiological parameters in combating COVID-19.

Chemokine CCL2 and its receptor CCR2 in different age groups of patients with COVID-19

BACKGROUND

Despite the development of various antiviral drugs, most of them are not effective in the treatment of coronavirus disease 2019 (COVID-19) as a hyperinflammatory disorder. Chemokine (C-C motif) ligand 2 (CCL2) is one of the critical CC chemokines involved in the pathogenesis and severity of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. This study aimed to investigate the expression of CCL2 and CC chemokine receptor 2 (CCR2) in COVID-19 patients.

METHODS

Peripheral blood samples were collected from 60 confirmed COVID-19 patients and 60 age-matched healthy subjects. The ages of the subjects were categorized as follows: up to 20 years, 20 to 40 years, 40 to 60 years, and more than 60 years. CCL2 serum levels were measured using the enzyme-linked immunosorbent assay (ELISA). CCR2 gene expression in peripheral blood mononuclear cells (PBMCs) was measured employing real-time polymerase chain reaction (PCR).

RESULTS

In all age groups, CCL2 serum levels were significantly elevated in patients compared to healthy controls (P < 0.0001). CCL2 levels were higher in severe patients than in moderate patients. Moreover, CCR2 expression by PBMCs was higher in patients compared to control subjects. However, a significant difference between patients and controls over 60 years of age was identified (P = 0.0353). There was no significant difference in CCR2 expression between moderate and severe COVID-19 patients.

CONCLUSIONS

Taken together, the findings demonstrate that CCL2 and CCR2 are upregulated in COVID-19 patients at protein and mRNA levels, respectively. Therefore, the CCL2/CCR2 axis may be a potential therapeutic target in order to improve patient outcomes.

Potential protective association of the AA genotype and a allele of CXCR4 rs2228014 polymorphism with COVID-19 severity in adult egyptians

BACKGROUND

By the end of December 2019, a new coronavirus, termed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged, and the cause of the disease was named coronavirus disease 2019 (COVID-19). Several genetic factors have been implicated in diverse responses to SARS-CoV-2 infection, such as the C-X-C chemokine receptor 4 (CXCR4) rs2228014 polymorphism, which has been previously studied in various diseases but has not been explored in the context of COVID-19 severity. The current study aimed to assess the association between the rs2228014 polymorphism in the CXCR4 gene and the severity of COVID-19, which has not been previously reported.

METHOD

This cross-sectional study analyzed 300 adult Egyptian COVID-19 patients (156 with mild or moderate and 144 with severe or critical symptoms) admitted to Assiut University Quarantine Hospital from June to September 2022 during the omicron variant. The rs2228014 polymorphism in the CXCR4 gene was detected using real-time PCR with a TaqMan assay probe. Receiver operating characteristic (ROC) curve analysis was used to determine the best cutoff values for C-reactive protein (CRP) that can be used to estimate the severity of COVID-19. P values less than 0.05 were considered to indicate statistical significance.

RESULTS

No significant differences in the allelic or genotypic frequencies of CXCR4 rs2228014 were detected between the severity groups. However, the exclusive presence of the AA genotype in mild or moderate cases suggests its potential protective role. Additionally, significant differences in myalgia presentation, leukocyte counts and antibiotic use, were observed among different genotypes. Statistical data showed that the severity of COVID-19 could be predicted at a cutoff value of CRP > 30 mg/L, with a sensitivity of 74.3% and a specificity of 42.9%.

CONCLUSION

The present findings suggest a potential protective role of the AA genotype and A allele of CXCR4 rs2228014 against severe COVID-19. Additionally, factors such as lack of vaccination and comorbidities such as hypertension, renal disease, and diabetes mellitus were associated with increased disease severity.

Association of Interleukin-6 (rs1800795) and Interleukin-10 (rs1800896) Genetic Polymorphisms with the Outcome of COVID-19 Infection: A Single Center Study

The corona virus disease-2019 (COVID-19) pandemic has affected most of the world with varying degrees of morbidity and mortality. The presence of genetic polymorphisms may be associated with the severity and outcome of COVID-19 infection. This work aimed to evaluate the genetic polymorphisms of interleukin (IL-6) and IL-10 genes with the outcome of COVID-19 infection. This cross-sectional study was conducted on 354 patients who were classified into moderate and severe cases (including alive and deceased cases). All individuals were genotyped for one SNP for IL-6 (rs1800795) and one SNP for IL10 (rs1800896) using allelic discrimination real-time PCR technique. In this study, 198 cases were moderate, and 156 cases were severe. The risk of allele carriage of the minor allele of IL-6 rs1800795 (C) was significantly higher among the severe group when compared with that of the moderate group (p < 0.0001), while there was a mild significant difference of same allele carriage among alive cases when compared to that of deceased one (p < 0.04). Furthermore, the risk of the C allele of IL-10 rs1800896 was significantly increased in severe cases when compared with the moderate group (p < 0.0001), while there was no significant difference of the risk of the C allele in deceased cases when compared with that of alive ones (p > 0.05). In conclusion, the C allele (rs1800795) of IL-6 and the C allele (rs1800896) of IL-10 were highly significant in severe cases than in moderate cases. The C allele carriage of IL-6 showed only a significant difference between alive and deceased patients and not with the C allele of IL-10.

Association between polymorphisms in TLR3, TICAM1 and IFNA1 genes and covid-19 severity in Southern Brazil

BACKGROUND

A distinct phenotype in Coronavirus disease 2019 (Covid-19) was observed in severe patients, consisting of a highly impaired interferon (IFN) type I response, an exacerbated inflammatory response.

OBJECTIVE

The aim of the present study was to investigate a possible association of single nucleotide polymorphisms (SNPs), in five genes related to the immune response, rs3775291 in TLR3; rs2292151 in TICAM1; rs1758566 in IFNA1; rs1800629 in TNF, and rs1800795 in IL6 with the severity of Covid-19.

METHODS

A cross-sectional study was performed, with non-severe and severe/critical patients diagnosed with Covid-19, by two public hospitals in Brazil. In total, 300 patients were genotyped for the SNPs, 150 with the non-severe form of the disease and 150 with severe/critical form.

RESULTS

The T/T genotype of TLR3 in recessive model shows 58% of protection against severe/critical Covid-19; as well as the genotypes G/A+A/A of TICAM1 in dominant model with 60% of protection, and in a codominant model G/A with 57% and A/A with 71% of protection against severe/critical Covid-19. Comparing severe and critical cases, the T/C genotype of IFNA1 in the codominant model and TC+C/C in the dominant model showed twice the risk of critical Covid-19.

CONCLUSION

We can conclude that rs3775291, rs2292151 and rs1758566 can influence the COVID-19 severity.

Association of TLR8 Variants in Sex-Based Clinical Differences in Patients with COVID-19

The host immune response might confer differential vulnerability to SARS-CoV-2 infection. The Toll-like receptor 8 (TLR8), could participated for severe COVID-19 outcomes. To investigated the relationship of TLR8 rs3764879-C/G, rs3764880-A/G, and rs3761624-A/G with COVID-19 outcomes and with biochemical parameters. A cross-sectional study of 830 laboratory-confirmed COVID-19 patients was performed, and classified into mild, severe, critical, and deceased outcomes. The TLR8 rs3764879-C/G, rs3764880-A/G, and rs3761624-A/G polymorphisms were genotyped. A logistic regression analysis was performed to determinate the association with COVID-19. A stratified analysis was by alleles was done with clinical and metabolic markets. In all outcomes, men presented the highest ferritin levels compared to women (P < 0.001). LDH levels were significantly different between sex in mild (P = 0.003), severe (P < 0.001) and deceased (P = 0.01) COVID-19 outcomes. The GGG haplotype showed an Odds Ratio of 1.55 (Interval Confidence 95% 1.05-2.32; P = 0.03) in men. Among patients with severe outcome, we observed that the carriers of the GGG haplotype had lower Ferritin, C-reactive protein and LDH levels than the CAA carriers (P < 0.01). After further stratified by sex, these associations were also seen in the male patients, except for D-dimer. Interestingly, among men patients, we could observe associations between TLR8 haplotypes and Ferritin (P < 0.001), D-dimer (P = 0.04), C-reactive protein, and Lactate dehydrogenase in mild (P = 0.04) group. Our results suggest that even though TLR8 haplotypes show a significant association with COVID-19 outcomes, they are associated with clinical markers in COVID-19 severity.

Study on the correlation between DPP9 rs2109069 and IFNAR2 rs2236757 polymorphisms with COVID-19 mortality

Understanding the complex mechanisms of the immune system in dealing with the COVID-19 infection, which is probably related to the polymorphism in cytokine and chemokine genes, can explain the pro-inflammatory condition of patients. Therefore, in this study, the relationship between the frequency of single nucleotide polymorphisms in the two pro-inflammatory genes dipeptidylpeptidase 9 (DPP9) and interferon alpha and beta receptor subunit 2 (IFNAR2) and the severity of COVID-19 was assessed. This study involved 954 COVID-19 patients, including 528 recovered and 426 deceased patients. To investigate the polymorphisms of IFNAR2 rs2236757 and DPP9 rs2109069, we used the polymerase chain reaction with the restriction fragment length polymorphism assay. The results showed that IFNAR2 rs2236757 A allele is related to the reduced severity of the disease, whereas the incidence of DPP9 rs2109069 A allele was higher among the deceased than recovered individuals. On the other hand, in people carrying the G allele in the DPP9 gene polymorphism and the allele A in the IFNR2 gene polymorphism, the improvement of the disease was significantly higher. In conclusion, the results showed that IFNAR2 rs2236757 A allele is related to the decrease in the severity of the disease, while the frequency of DPP9 rs2109069 A allele was higher in deceased people than in recovered people. This shows the important role of genes related to inflammatory responses as well as the role of genetic variants of these genes in the severity of COVID-19.

IL-18 and CD14 variants in chronic HBV predisposition: a case-control study with in silico analyses focused on transcription and splicing

Hepatitis B virus (HBV), a vaccine-avoidable infection, is a health concern worldwide, leading to liver disorders such as acute self-constraint and chronic hepatitis, liver failure, hepatic cirrhosis, and even hepatocellular carcinoma if untreated. 'Immunogeneticprofiling', genetic variations of the pro- and anti-inflammatory cytokines responsible for regulating the immune responses, cause person-to-person differences and impact the clinical manifestation of the disease. The current experimental-bioinformatics research was conducted to examine whether promoteric IL-18-rs187238 C > G and -rs1946518 T > G and intronic CD14-rs2569190 A > G variations are associated with chronic HBV. A total of 400 individuals (200 in each case and control group) participated in the study and were genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. The data was also assessed bioinformatics-wise for conservation, genomic transcription and splicing, and protein interactions. Findings proposed that unlike the IL-18-rs1946518 T > G and CD14-rs2569190 A > G, the IL-18-rs187238 C > G is a protector against chronic HBV (odds ratio [OR] = 0.62, 95% confidence intervals [CI]: 0.46-0.83, and p = 0.002). The TG/CC/AA, TG/CC/AG, TT/CC/AG, and GG/CC/AA combined genotypes significantly increased chronic HBV risk (p < 0.05), while the IL-18 G/T and G/G haplotypes lessened it (p < 0.05). Moreover, IL-18-rs1946518 T > G is in the protected genomic regions across mammalian species. In contrast to the IL-18-rs1946518 T > G, IL-18-rs187238 C > G is likely to create novel binding sites for transcription factors, and the CD14-rs2569190 A > G presumably changed the ribonucleic acid splicing pattern. More research on larger populations and other ethnicities is required to authenticate these results.

Genetic polymorphisms of ACE1, ACE2, IFTM3, TMPRSS2 and TNFα genes associated with susceptibility and severity of SARS-CoV-2 infection: a systematic review and meta-analysis

BACKGROUND

Some human polymorphisms of ACE1, ACE2, IFITM3, TMPRSS2 and TNFα genes may have an effect on the susceptibility to SARS-CoV-2 infection and increase the risk to develop severe COVID-19. We conducted a systematic review of current evidence to investigate the association of genetic variants of these genes with the susceptibility to virus infection and patient prognosis.

METHODS

We systematically searched Medline, Embase and The Cochrane Library for articles published until May 2022, and included observational studies covering genetic association of ACE1, ACE2, IFITM3, TMPRSS2 and TNFα genes with COVID-19 susceptibility or prognosis. We evaluated the methodological quality of included studies, and pooled data as convenient in meta-analysis (MA). Odds ratio (OR) values and 95% confidence intervals were calculated.

RESULTS

We included 35 studies (20 on ACE, 5 each on IFITM3, TMPRSS2, TNFα), enrolling 21,452 participants, of them 9401 were COVID-19 confirmed cases. ACE1 rs4646994 and rs1799752, ACE2 rs2285666, TMPRSS2 rs12329760, IFITM3 rs12252 and TNFα rs1800629 were identifies as common polymorphisms. Our MA showed an association between genetic polymorphisms and susceptibility to SARS-CoV-2 infection for IFITM3 rs12252 CC (OR 5.67) and CT (OR 1.64) genotypes. Furthermore, MA uncovered that both ACE DD (OR 1.27) and IFITM3 CC (OR 2.26) genotypes carriers had a significantly increased risk of developing severe COVID-19.

DISCUSSION

These results provide a critical evaluation of genetic polymorphisms as predictors in SARS-CoV-2 infection. ACE1 DD and IFITM3 CC polymorphisms would lead to a genetic predisposition for severe lung injury in patients with COVID-19.

Spotlight on contributory role of host immunogenetic profiling in SARS-CoV-2 infection: Susceptibility, severity, mortality, and vaccine effectiveness

BACKGROUND

The SARS-CoV-2 virus has spread continuously worldwide, characterized by various clinical symptoms. The immune system responds to SARS-CoV-2 infection by producing Abs and secreting cytokines. Recently, numerous studies have highlighted that immunogenetic factors perform a putative role in COVID-19 pathogenesis and implicate vaccination effectiveness.

AIM

This review summarizes the relevant articles and evaluates the significance of mutation and polymorphism in immune-related genes regarding susceptibility, severity, mortality, and vaccination effectiveness of COVID-19. Furthermore, the correlation between host immunogenetic and SARS-CoV-2 reinfection is discussed.

METHOD

A comprehensive search was conducted to identify relevant articles using five databases until January 2023, which resulted in 105 total articles.

KEY FINDINGS

Taken to gather this review summarized that: (a) there is a plausible correlation between immune-related genes and COVID-19 outcomes, (b) the HLAs, cytokines, chemokines, and other immune-related genes expression profiles can be a prognostic factor in COVID-19-infected patients, and (c) polymorphisms in immune-related genes have been associated with the effectiveness of vaccination.

SIGNIFICANCE

Regarding the importance of mutation and polymorphisms in immune-related genes in COVID-19 outcomes, modulating candidate genes is expected to help clinical decisions, patient outcomes management, and innovative therapeutic approach development. In addition, the manipulation of host immunogenetics is hypothesized to induce more robust cellular and humoral immune responses, effectively increase the efficacy of vaccines, and subsequently reduce the incidence rates of reinfection-associated COVID-19.

Identifying signatures of positive selection in human populations from North Africa

Because of its location, North Africa (NA) has witnessed continuous demographic movements with an impact on the genomes of present-day human populations. Genomic data describe a complex scenario with varying proportions of at least four main ancestry components: Maghrebi, Middle Eastern-, European-, and West-and-East-African-like. However, the footprint of positive selection in NA has not been studied. Here, we compile genome-wide genotyping data from 190 North Africans and individuals from surrounding populations, investigate for signatures of positive selection using allele frequencies and linkage disequilibrium-based methods and infer ancestry proportions to discern adaptive admixture from post-admixture selection events. Our results show private candidate genes for selection in NA involved in insulin processing (KIF5A), immune function (KIF5A, IL1RN, TLR3), and haemoglobin phenotypes (BCL11A). We also detect signatures of positive selection related to skin pigmentation (SLC24A5, KITLG), and immunity function (IL1R1, CD44, JAK1) shared with European populations and candidate genes associated with haemoglobin phenotypes (HPSE2, HBE1, HBG2), other immune-related (DOCK2) traits, and insulin processing (GLIS3) traits shared with West and East African populations. Finally, the SLC8A1 gene, which codifies for a sodium-calcium exchanger, was the only candidate identified under post-admixture selection in Western NA.

Influence of polymorphic variations of IFNL, HLA, and IL-6 genes in severe cases of COVID-19

The administration of vaccination doses to the global population has led to a decrease in the incidence of COVID-19. However, the clinical picture developed by infected individuals remains extremely concerning due to the great variability in the severity of cases even in vaccinated individuals. The clinical progression of the pathology is characterized by various influential factors such as sex, age group, comorbidities, and the genetics of the individual. The immune response to viral infections can be strongly influenced by the genetics of individuals; nucleotide variations called single-nucleotide polymorphisms (SNPs) in structures involved in the innate and adaptive immune response such as interferon (IFN)-λ, human leukocyte antigen (HLA), and interleukin (IL)-6 are frequently associated with pathological progression. In this study, we conducted a review of the main SNPs of these structures that are associated with severity in COVID-19. Searches were conducted on some platforms of the National Center for Biotechnology and Information (NCBI), and 102 studies were selected for full reading according to the inclusion criteria. IFNs showed a strong association with antiviral function, specifically, IFN-λ3 (IL-28B) demonstrated genetic variants commonly related to clinical progression in various pathologies. For COVID-19, rs12979860 and rs1298275 presented frequently described unfavorable genotypes for pathological conditions of hepatitis C and hepatocellular carcinoma. The high genetic variability of HLA was reported in the studies as a crucial factor relevant to the late immune response, mainly due to its ability to recognize antigens, with the HLA-B*46:01 SNP being associated with susceptibility to COVID-19. For IL-6, rs1554606 showed a strong relationship with the clinical progression of COVID-19. In addition, rs2069837 was identified with possible host protection relationships when linked to this infection.

Investigation of the relationship between IL17A, IL17F and ILR1N polymorphisms and COVID-19 severity: The predictive role of IL17A rs2275913 polymorphism in the clinical course of COVID-19

Coronavirus disease 2019 (COVID-19) is an infectious respiratory disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although the mortality rate of the disease has been relatively under control as of 2022, more than 15 million confirmed COVID-19 cases have been detected in Turkey to date, causing more than 100,000 deaths. The clinical manifestation of the disease varies widely, ranging from asymptomatic to acute respiratory distress syndrome causing death. The immune response mechanisms have an important impact on the fine adjustment between healing and enhanced tissue damage. This study aims to investigate the relationship between the variants of the interleukin 1 receptor antagonist (IL1RN), interleukin 17A (IL17A), and interleukin 17F (IL17F) genes and COVID-19 severity. The study population comprised 202 confirmed COVID-19 cases divided into three groups according to severity. The IL1RN variable number of a tandem repeat (VNTR) polymorphism was genotyped by polymerase chain reaction (PCR), and IL17A rs2275913, IL17F rs763780 and rs2397084 polymorphisms were genotyped by the PCR-based restriction fragment length polymorphism method. Statistical analysis revealed a significant association between IL17A rs2275913 variant and COVID-19 severity. The AA genotype and the A allele of IL17A rs2275913 were found significant in the severe group. Additionally, we found a significant relationship between haplotype frequency distributions and severity of COVID-19 for the IL17F rs763780/rs2397084 (p = 0.044) and a combination of IL17F rs763780/rs2397084/ IL17A rs2275913 (p = 0.04). The CG and CGA haplotype frequencies were significantly higher in the severe group. IL17A rs2275913, IL17F rs763780 and rs2397084 variants appear to have important effects on the immune response in COVID-19. In conclusion, variants of IL17A rs2275913, IL17F rs763780 and rs2397084 may be the predictive markers for the clinical course and potential immunomodulatory treatment options in COVID-19, a disease that has placed a significant burden on our country.

Age and Cytokine Gene Variants Modulate the Immunogenicity and Protective Effect of SARS-CoV-2 mRNA-Based Vaccination

The introduction of anti-SARS-CoV-2 vaccines in late 2020 substantially changed the pandemic picture, inducing effective protection in the population. However, individual variability was observed with different levels of cellular response and neutralizing antibodies. We report data on the impact of age, gender, and 16 single nucleotide polymorphisms (SNPs) of cytokine genes on the anti-SARS-CoV-2 IgG titers measured 31 and 105 days after administration of the second dose of BNT162b2 vaccine to 122 healthy subjects from the health care staff of the Palermo University Hospital, Italy. The higher titers at 31 days were measured in the younger subjects and in subjects bearing T-positive genotypes of IL-1R1 rs2234650 or the GG homozygous genotype of IL-6 rs1800795 SNP. T-positive genotypes are also significantly more common in subjects with higher titers at day 105. In addition, in this group of subjects, the frequency of the CT genotype of IL-4 rs2243250 is higher among those vaccinated with higher titers. Moreover, these SNPs and TNFA rs1800629 are differently distributed in a group of subjects that were found infected by SARS-CoV-2 at day 105 of evaluation. Finally, subjects that were found to be infected by SARS-CoV-2 at day 105 were significantly older than the uninfected subjects. Taken together, these data seem to suggest that age and polymorphisms of key cytokines, which regulate inflammation and humoral immune response, might influence the magnitude of the antibody response to vaccination with BNT162B2, prompting speculation about the possible benefit of a genetic background-based assessment of a personalized approach to the anti-COVID vaccination schedule.

Association of Tumor Necrosis Factor-Alpha (TNF-α) and Suppressor of Cytokine Signaling-1 (SOCS-1) Gene Variants in Children with COVID-19

Objective The suppressor of cytokine signaling-1 (SOCS-1) gene is an essential physiological regulator of cytokine signaling. Tumor necrosis factor-α (TNF-α) is an important component of the immunological response. Herein, we aimed to investigate the effects of SOCS-1 (-1478 CA > Del) and TNF-α (-308) polymorphisms on disease susceptibility and prognosis in pediatric patients with coronavirus disease 2019 (COVID-19).

Methods One-hundred fifty COVID-19 patients in the COVID-19 emergency department between September 2020 and April 2021 and 80 healthy volunteers (control group) without any additional disease were included. Baseline gene polymorphisms were compared between the patient and healthy control groups. Afterward, the gene polymorphism distribution was examined by forming two separate clinical patients' subgroups.

Results While CA/CA and CA/Del gene variants of SOCS-1 were higher in the patient group, Del/Del genotype was more common in the control group (p < 0.05). The GG genotype of the TNF-α was significantly more common in the severe subgroup (p = 0.044). The GA genotype of TNF-α was associated with the risk of hospitalization (2.83-fold), while the GG genotype was found to be protective in terms of hospitalization (2.95-fold).

Conclusions This study will be a guide in terms of the presence of high cytokine release genotypes and COVID-19-related cytokine release syndromes.

IL6R gene polymorphisms and their relation to chronic obstructive pulmonary disease susceptibility in the Chinese population

Background: This work was designed to explore the correlation between IL6R polymorphisms and chronic obstructive pulmonary disease (COPD) susceptibility. Methods: Agena MassARRAY was used to genotype five SNPs of IL6R in 498 patients with COPD and 498 controls. Genetic models and haplotype analysis were used to assess the associations between SNPs and COPD risk. Results: Rs6689306 and rs4845625 increase the risk of COPD. Rs4537545, rs4129267 and rs2228145 were related to a decreased risk of COPD in different subgroups. Haplotype analysis revealed that GTCTC, GCCCA and GCTCA contributed to a reduced risk of COPD after adjustment. Conclusion: IL6R polymorphisms are significantly associated with COPD susceptibility.

Analysis of Gene Single Nucleotide Polymorphisms in COVID-19 Disease Highlighting the Susceptibility and the Severity towards the Infection

Many factors may influence the risk of being infected by SARS-CoV-2, the coronavirus responsible for coronavirus disease 2019 (COVID-19). Exposure to the virus cannot explain the variety of an individual's responses to the virus and the high differences of effect that the virus may cause to some. While a person's preexisting condition and their immune defenses have been confirmed to play a major role in the disease progression, there is still much to learn about hosts' genetic makeup towards COVID-19 susceptibility and risk. The host genetic makeup may have direct influence on the grade of predisposition and outcomes of COVID-19. In this study, we aimed to investigate the presence of relevant genetic single nucleotide polymorphisms (SNPs), the peripheral blood level of IL6, vitamin D and arterial blood gas (ABG) markers (pH, oxygen-SpO₂ and carbon dioxide-SpCO₂) on two groups, COVID-19 (n = 41, study), and the healthy (n = 43, control). We analyzed cytokine and interleukin genes in charge of both pro-inflammatory and immune-modulating responses and those genes that are considered involved in the COVID-19 progression and complications. Thus, we selected major genes, such as IL1β, IL1RN (IL-1 β and α receptor) IL6, IL6R (IL-6 receptor), IL10, IFNγ (interferon gamma), TNFα (tumor necrosis factor alpha), ACE2 (angiotensin converting enzyme), SERPINA3 (Alpha-1-Antiproteinase, Antitrypsin member of Serpin 3 family), VDR (vitamin D receptor Tak1, Bsm1 and Fok1), and CRP (c-reactive protein). Though more research is needed, these findings may give a better representation of virus pleiotropic activity and its relation to the immune system.

Single-Cell Gene Expression Analysis Revealed Immune Cell Signatures of Delta COVID-19

The coronavirus disease 2019 (COVID-19) is accompanied by a cytokine storm with the release of many proinflammatory factors and development of respiratory syndrome. Several SARS-CoV-2 lineages have been identified, and the Delta variant (B.1.617), linked with high mortality risk, has become dominant in many countries. Understanding the immune responses associated with COVID-19 lineages may therefore aid the development of therapeutic and diagnostic strategies. Multiple single-cell gene expression studies revealed innate and adaptive immunological factors and pathways correlated with COVID-19 severity. Additional investigations covering host–pathogen response characteristics for infection caused by different lineages are required. Here, we performed single-cell transcriptome profiling of blood mononuclear cells from the individuals with different severity of the COVID-19 and virus lineages to uncover variant specific molecular factors associated with immunity. We identified significant changes in lymphoid and myeloid cells. Our study highlights that an abundant population of monocytes with specific gene expression signatures accompanies Delta lineage of SARS-CoV-2 and contributes to COVID-19 pathogenesis inferring immune components for targeted therapy.

Inflammasome Genetic Variants Are Associated with Protection to Clinical Severity of COVID-19 among Patients from Rio de Janeiro, Brazil

COVID-19 has a broad spectrum of clinical manifestations, from asymptomatic or mild/moderate symptoms to severe symptoms and death. The mechanisms underlying its clinical evolution are still unclear. Upon SARS-CoV-2 infection, host factors, such as the inflammasome system, are activated by the presence of the virus inside host cells. The search for COVID-19 risk factors is of relevance for clinical management. In this study, we investigated the impact of inflammasome single-nucleotide polymorphisms (SNPs) in SARS-CoV-2-infected individuals with distinct severity profiles at clinical presentation. Patients were divided into two groups according to disease severity at clinical presentation based on the WHO Clinical Progression Scale. Group 1 included patients with mild/moderate disease (WHO < 6; n = 76), and group 2 included patients with severe/critical COVID-19 (WHO ≥ 6; n = 357). Inpatients with moderate to severe/critical profiles were recruited and followed-up at Hospital Center for COVID-19 Pandemic – National Institute of Infectology (INI)/FIOCRUZ, RJ, Brazil, from June 2020 to March 2021. Patients with mild disease were recruited at Oswaldo Cruz Institute (IOC)/FIOCRUZ, RJ, Brazil, in August 2020. Genotyping of 11 inflammasome SNPs was determined by real-time PCR. Protection and risk estimation were performed using unconditional logistic regression models. Significant differences in NLRP3 rs1539019 and CARD8 rs2043211 were observed between the two groups. Protection against disease severity was associated with the A/A genotype (OR_adj = 0.36; P = 0.032), allele A (OR_adj = 0.93; P = 0.010), or carrier-A (OR_adj = 0.45; P = 0.027) in the NLRP3 rs1539019 polymorphism; A/T genotype (OR_adj = 0.5; P = 0.045), allele T (OR_adj = 0.93; P = 0.018), or carrier-T (OR_adj = 0.48; P = 0.029) in the CARD8 rs2043211 polymorphism; and the A-C-G-C-C (OR_adj = 0.11; P = 0.018), A-C-G-C-G (OR_adj = 0.23; P = 0.003), C-C-G-C-C (OR_adj = 0.37; P = 0.021), and C-T-G-A-C (OR_adj = 0.04; P = 0.0473) in NLRP3 genetic haplotype variants. No significant associations were observed for the other polymorphisms. To the best of our knowledge, this is the first study demonstrating an association between CARD8 and NLRP3 inflammasome genetic variants and protection against COVID-19 severity, contributing to the discussion of the impact of inflammasomes on COVID-19 outcomes.