A common functional polymorphism (C-->A substitution at position -863) in the promoter region of the tumour necrosis factor-alpha (TNF-alpha) gene associated with reduced circulating levels of TNF-alpha

The Genetic Variant TNFA (rs361525) Is Associated with Increased Susceptibility to Developing Dengue Symptoms

Dengue virus (DENV) is the causal agent of dengue fever. The symptoms and signs of dengue vary from febrile illness to hemorrhagic syndrome. IFITM3 and TNFA are genes of the innate immune system. Variants IFITM3 (rs12252 T>C) and TNFA (rs1800629 G > A and rs361525 G>A) might alter gene expression and change the course of the disease. Our first objective was to determine whether these variants were associated with the susceptibility and severity of dengue. The second was to assess the association of these variants with each symptom. We studied 272 cases with suspected dengue infection, of which 102 were confirmed dengue cases (DENV+) and 170 were dengue-like cases without DENV infection (DENV-). Samples of 201 individuals from the general population of Mexico were included as a reference. Genotyping was performed by the polymerase chain reaction-restriction fragment length polymorphism technique. Odds ratios and confidence intervals were calculated using Pearson's chi-square test and later adjusted for age and sex with a binary logistic regression model. Haldane correction is applied when necessary. We found a significantly higher frequency of the A allele of TNFA rs361525 in both the DENV+ and DENV- groups compared with the general population. Focusing on DENV+ and DENV-, the frequency of the A allele of TNFA rs361525 was higher in the DENV+ group. A broad spectrum of symptoms was related to the A allele of both TNFA variants. We conclude that TNFA rs361525 increases the susceptibility to symptomatic dengue but can also be associated with susceptibility to other dengue-like symptoms from unknown causes.

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.

Marked to Die-Cell Death Mechanisms for Keratinocyte Acantholysis in Pemphigus Diseases

Pemphigus is a group of blistering autoimmune diseases causing painful skin lesions, characterized by acantholysis and by the production of autoantibodies against, mainly, adhesion proteins. We reviewed the literature for molecules and/ or features involved in the 12 cell death pathways described by Nomenclature Committee on Cell Death, taking place in pemphigus patients, cell lines, or human skin organ cultures treated with sera or IgG from pemphigus patients or in pemphigus mouse models, and found 61 studies mentioning 97 molecules involved in cell death pathways. Among the molecules, most investigated were pleiotropic molecules such as TNF and CASP3, followed by FASL and CASP8, and then by FAS, BAX, BCL2, and TP53, all involved in more than one pathway but interpreted to function only within apoptosis. Most of these previous investigations focused only on apoptosis, but four recent studies, using TUNEL assays and/or electron microscopy, disqualified this pathway as a previous event of acantholysis. For PV, apoptolysis was suggested as a cell death mechanism based on pathogenic autoantibodies diversity, mitochondrial dysfunction, and p38 MAPK signaling. To answer those many questions that remain on cell death and pemphigus, we propose well-controlled, statistically relevant investigations on pemphigus and cell death pathways besides apoptosis, to overcome the challenges of understanding the etiopathology of pemphigus diseases.

Will a little change do you good? A putative role of polymorphisms in COVID-19

An alarming disease caused by the new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) named COVID-19 has emerged as an unprecedented public health problem and ignited a world health crisis. As opposed to what was believed at the beginning of the pandemic, the virus has not only spread but persevere causing secondary waves and challenging the concept of herd immunity against viral infections. While the majority of SARS-CoV-2-infected individuals may remain asymptomatic, a fraction of individuals may develop low to high-grade severity signs and symptoms of COVID-19. The disease is multifactorial and can progress quickly, leading to severe complications and even death in a few days. Therefore, understanding the pre-existing factors for disease development has never been so pressing. In this scenario, the insights on the mechanisms underlying disease allied to the immune response developed during the viral invasion could shed light on novel predictive factors and prognostic tools for COVID-19 management and interventions. A recent genome-wide association study (GWAS) revealed several molecules that significantly impacted critically ill COVID-19 patients, leading to the core mechanisms of COVID-19 pathogenesis. Considering these findings and the fact that ACE-2 polymorphisms alone cannot explain disease progress and severity, this review aims at summarizing the most important and recent findings of the research and expert consensus of possible cytokine-related polymorphisms existing in the differential expression of paramount immune molecules that could be crucial for providing guidelines for decision-making and appropriate clinical management of COVID-19.

SNPs in genes encoding for IL-10, TNF-α, and NFκB p105/p50 are associated with clinical prognostic factors for patients with Hodgkin lymphoma

Classical Hodgkin lymphoma (cHL) is a B-cell-derived malignant neoplasia that has a unique histological distribution, in which the scarce malignant Hodgkin and Reed-Sternberg cells are surrounded by nonmalignant inflammatory cells. The interactions between the malignant and inflammatory cells are mediated by aberrantly produced cytokines, which play an important role in tumor immunopathogenesis. Single nucleotide polymorphisms (SNPs) in genes encoding cytokines and their regulatory proteins may influence the peripheral levels of these molecules and affect disease’s pathobiology. In this study, we evaluate SNPs in the promoter regions of the genes encoding for two key cytokines in Hodgkin lymphoma: IL-10 (SNP/pIL10–592, rs1800872; and SNP/pIL10–1082, rs1800896) and TNF-α (SNP/pTNF -238, rs361525; and SNP/pTNF -862, rs1800630), as well as an SNP in the intronic region of the NFκB1 gene (SNP/iNFKB1, rs1585215), an important regulator of cytokine gene expression. We then look to their possible association with clinical and laboratory features in cHL patients. Seventy-three patients with cHL are genotyped by qPCR-high resolution melting. The SNPs’ genotypes are analyzed individually for each SNP, and when more than two allelic combinations are identified, the genotypes are also divided into two groups according to proposed biological relevance. By univariate analysis, patients harboring SNP/pTNF -238 AG genotype more frequently have EBV-associated cHL compared to homozygous GG, whereas the presence of mediastinal disease (bulky and nonbulky) is more common in the pIL10–592 AC/CC group compared to the AA homozygous group. Patients with SNP/iNFKB1 AA genotype more frequently have stage IV and extranodal disease at diagnosis. These results indicate that some SNPs’ genotypes for IL-10 and TNF-α genes are associated with prognostic parameters in cHL. For the first time, the SNP/iNFKB1 is described in association with clinical features of the disease.

Association between five types of Tumor Necrosis Factor-α gene polymorphism and hepatocellular carcinoma risk: a meta-analysis

BACKGROUND

Research focusing on the relationship between five types of tumor necrosis factor-alpha (TNF-α) SNPs and the risk of hepatocellular carcinoma (HCC) were still controversial. Hereby, we performed a meta-analysis to determine the association between TNF-α promoter SNPs: -1031 T/C, - 863 C/A, - 857 C/T, - 308 G/A, and - 238 G/A with HCC risk.

METHODS

We interrogated articles from journal database: PubMed, Pro-Quest, EBSCO, Science Direct, and Springer to determine the relationship between five types of SNPs in TNF-α gene with HCC risk. RevMan 5.3 software was used for analysis in fixed/random effect models.

RESULTS

This meta-analysis included 23 potential articles from 2004 to 2018 with 3237 HCC cases and 4843 controls. We found that SNP - 863 C/A were associated with a significantly increased HCC risk (A vs C, OR = 1.31, 95% CI = 1.03-1.67). Similar results were obtained in - 857 C/T (TT/CT vs CC, OR = 1.31, 95% CI = 1.06-1.62), - 308 G/A (AA vs GG, OR = 3.14, 95% CI = 2.06-4.79), and - 238 G/A (AA vs GG, OR = 3.87, 95% CI = 1.32-11.34). While no associations were observed between SNP TNF-α - 1031 T/C and HCC risk.

CONCLUSIONS

The present meta-analysis showed that TNFα SNPs -863C/A, - 857 C/T, - 308 G/A, and - 238 G/A were associated with the risk of HCC.

Effects of TNF-α-308G/A Polymorphism on the Risk of Diabetic Nephropathy and Diabetic Retinopathy: An Updated Meta-Analysis

Diabetic nephropathy (DN) and diabetic retinopathy (DR) are the major factors of morbidity and mortality in the patients with diabetes mellitus (DM). Growing studies have investigated the relationship between the TNF-α-308G/A polymorphism and the susceptibility to DN and DR, without achieving consensus. Thus, we conducted this meta-analysis to reach more comprehensive conclusions for these issues. Eligible studies were retrieved through electronic databases such as PubMed, Embase, Web of Science and China National Knowledge Infrastructure. Summary of odds ratios (OR) and 95% confidence intervals (CIs) were generated to evaluate the intensity of the associations. Statistical analyses were performed by STATA 11.0 and RevMan 5.2. There are fourteen eligible publications involving nineteen studies in this meta-analysis. TNF-α-308G/A polymorphism was significantly related to increasing risk of DN under recessive model (OR=1.37, 95% CI=1.03-1.83) and homozygous model (OR=1.54, 95% CI=1.15-2.06). Moreover, the similar results were also obtained in Asian groups for DN (recessive: OR=1.69, 95% CI=1.18-2.42; homozygous: OR=1.99, 95% CI=1.38-2.86; respectively), and significant association was also detected between TNF-α-308G/A and DN susceptibility in type 2 DM in recessive model (OR=1.39, 95% CI=1.02-1.89). No significant association was observed between TNF-α-308G/A and DR susceptibility in total analyses and subgroup analyses by ethnicity and type of DM. TNF-α-308G/A polymorphism may enhance the susceptibility to diabetic nephropathy, especially in Asian population and in T2DM patients, but not diabetic retinopathy.

Association of TNF-α-308G/A, -238G/A, -863C/A, -1031T/C, -857C/T polymorphisms with periodontitis susceptibility: Evidence from a meta-analysis of 52 studies

The association between tumor necrosis factor-alpha (TNF-α-308G/A, -238G/A, -863C/A, -1031T/C, and -857C/T) polymorphism and either chronic (CP) or aggressive (AgP) periodontitis susceptibility was conflicting. This meta-analysis aimed to quantitatively estimate the association.A total of 52 studies involving 5519 patients and 7260 controls were identified through a search of multiple electronic databases. Odds ratios (ORs) and their 95% confidence intervals using allele, homozygous, heterozygous, dominant, and recessive genetic models were computed to assess the strength of the association.The TNF-α-308G/A polymorphism was significantly associated with decreased risks of CP (GG vs AA: OR = 0.353, P < .001; GG+GA vs AA: OR = 0.480, P < .001) and AgP (G vs A: OR = 0.651, P < .001; GG vs AA: OR = 0.306, P < .001; GG+GA vs AA: OR = 0.384, P < .001) in Asians. There were no associations between TNF-α-238G/A, -863C/A, -1031T/C, -857C/T polymorphism and susceptibility to AgP. No associations were also found between CP susceptibility and TNF-α-238G/A, -857C/T polymorphism.These findings supported that TNF-α-308G/A polymorphism might be the protective factors of CP and AgP in Asians, and TNF-α-238G/A, -863C/A, -1031T/C, -857C/T polymorphism is not linked to AgP susceptibility.

Advances in our understanding of gout as an auto-inflammatory disease

Gout, the most common inflammatory arthritis, is the result of hyperuricemia and inflammation induced by monosodium urate (MSU) crystal deposition. However, most people with hyperuricemia will never develop gout, implying a molecular-genetic contribution to the development of gout. Recent genomic studies reveal links between certain genetic variations and gout. We highlight recent advances in our understanding of gout as an auto-inflammatory disease. We review the auto-inflammatory aspects of gout, including the inflammasome and thirteen gout-associated inflammatory-pathway genes and associated comorbidities. This information provides important insights into emerging immune-modulating targets in the management of gout, and future novel therapeutic targets in gout treatment. Cumulatively, this has important implications for treating gout as an auto-inflammatory disease, as opposed to a purely metabolic disease.

Condemned or Not to Die? Gene Polymorphisms Associated With Cell Death in Pemphigus Foliaceus

Pemphigus foliaceus (PF) is an autoimmune blistering skin disease that occurs sporadically across the globe and is endemic in Brazil. Keratinocyte adhesion loss (acantholysis) is associated with high levels of anti-desmoglein 1 IgG autoantibodies, but the role of cell death is poorly understood in PF. Current evidence disqualifies apoptosis as the major cell death mechanism and no other process has yet been investigated. To approach the role of variation in genes responsible for cell death pathways in pemphigus susceptibility, we systematically investigated the frequencies of 1,167 polymorphisms from genes encoding products of all 12 well-established cell death cascades (intrinsic and extrinsic apoptosis, necrosis, necroptosis, ferroptosis, pyroptosis, parthanatos, entotic, NETotic, lysosome-dependent, autophagy-dependent, and immunogenic). By multivariate logistic regression, we compared allelic and genotypic frequencies of 227 PF patients and 194 controls obtained by microarray hybridization. We found 10 variants associated with PF (p < 0.005), belonging to six cell death pathways: apoptosis (TNF, TRAF2, CD36, and PAK2), immunogenic cell death (EIF2AK3, CD47, and SIRPA), necroptosis (TNF and TRAF2), necrosis (RAPGEF3), parthanatos (HK1), and pyroptosis (PRKN). Five polymorphisms were associated with susceptibility: TNF rs1800630*A (OR = 1.9, p = 0.0003), CD36 rs4112274*T (OR = 2.14, p = 0.0015), CD47 rs12695175*G (OR = 1.77, p = 0.0043), SIRPA rs6075340*A/A (OR = 2.75, p = 0.0009), and HK1 rs7072268*T (OR = 1.48, p = 0.0045). Other five variants were associated with protection: TRAF2 rs10781522*G (OR = 0.64, p = 0.0014), PAK2 rs9325377*A/A (OR = 0.48, p = 0.0023), EIF2AK3 rs10167879*T (OR = 0.48, p = 0.0007), RAPGEF3 rs10747521*A/A (OR = 0.42, p = 0.0040), and PRKN rs9355950*C (OR = 0.57, p = 0.0004). Through functional annotation, we found that all associated alleles, with the exception of PRKN rs9355950*C, were previously associated with differential gene expression levels in healthy individuals (mostly in skin and peripheral blood). Further functional validation of these genetic associations may contribute to the understanding of PF etiology and to the development of new drugs and therapeutic regimens for the disease.

Association of TNF-α gene alterations (c.-238G>A, c.-308G>A, c.-857C>T, c.-863C>A) with primary glaucoma in north Indian cohort

BACKGROUND

Tumor Necrosis Factor-alpha (TNF-α) a pleuripotent pro-inflammatory cytokine, is involved in retinal ganglion cells apoptosis in glaucoma. Thus present study aimed to analyze the association of TNF-α promoter region alterations (c.-238G>A (rs361525), c.-308G>A (rs1800629), c.-857C>T (rs1799724) and c.-863C>A (rs1800630)) with glaucoma in north Indian cohort.

METHODS

Present hospital based case control study involved 286 glaucoma patients (Primary Open Angle Glaucoma [POAG], Primary Angle Closure Glaucoma [PACG], Primary Congenital Glaucoma [PCG]) and 300 controls. TNF-α gene alteration (c.-238G>A (also referred as c.-418G>A; NM_000594.3)), c.-308G>A (c.-488G>A; NM_000594.3), c.-857C>T (c.-1037C>T; NM_000594.3) and c.-863C>A (c.-1043C>A; NM_000594.3) harboring regions were PCR amplified and sequenced by Sanger sequencing. Allele frequency and genotype distribution in glaucoma cases and controls were compared using chi-square test and genetic association tested using different genetic models.

RESULTS

Statistically significant genotype and allelic association was observed between glaucoma cases and controls for c.-308G>A and c.-863C>A alterations (p = 0.001, p = 0.001; p = 0.001, p = 0.001 respectively). AA genotype of c.-308G>A conferred ~7 fold increased risk towards glaucoma (OR = 6.82, 95% CI = 2.82-16.53, p = 0.001). c.-863C>A alteration under dominant, recessive and co-dominant genetic models conferred ~2 fold increased risk for glaucoma. However, no association for c.-238G>A and c.-857C>T variants with glaucoma was observed. Further, three haplotypes (GGCA, GACC and GACA) (OR = 0.48, 95% CI = 0.35-0.67, p = 0.001; OR = 0.58, 95% CI = 0.36-0.91, p = 0.019 and OR = 0.16, 95% CI = 0.05-0.51, p = 0.002, respectively) conferred protective role towards glaucoma.

CONCLUSIONS

Present study is the first to indicate significant association of c.-308G>A and c.-863C>A alterations with glaucoma in cases from north Indian cohort. Also it is the first study from India to analyze the association and interaction of four promoter region alterations (c.-238G>A, c.-308G>A, c.-857C>T and c.-863C>A) in TNF-α resulting in three protective haplotypes.

The associations of TNF-α gene polymorphisms with bone mineral density and risk of osteoporosis: A meta-analysis

OBJECTIVE

Fracture is a common consequence of osteoporosis and is associated with high morbidity and mortality. Recently, increasing evidence has suggested that polymorphisms in tumor necrosis factor-α (TNF-α) gene were associated with osteoporosis risk and bone mineral density (BMD), but results remain conflicting. We herein performed a meta-analysis based on evidence currently available from the literature to make a more precise estimation of these relationships.

METHODS

The PubMed, EMBASE, Cochrane Library, CNKI (China National Knowledge Infrastructure) and Wan Fang databases were searched for eligible studies. Articles meeting the inclusion criteria were comprehensively reviewed and all available data were accumulated. The pooled odds ratios (ORs) or mean differences (MDs) and corresponding 95% confidence intervals (CIs) were applied to assess the strength of the relationships.

RESULTS

A total of 15 studies involving 5273 subjects were included in our meta-analysis. The GG genotype of TNF-α G308A was associated with an increased risk of osteoporosis under a mutant model (GG vs GA+AA: OR = 0.63, 95% CI: 0.51-0.77, P < 0.0001, I²  = 31%). Additionally, we also observed a significant association between G308A polymorphism and BMD of lumbar spine (AA vs GG: P = 0.01, I²  = 53%). However, TNF-α T1031C, C857T and C863A polymorphisms had no obvious impacts on osteoporosis risk.

CONCLUSIONS

The present meta-analysis demonstrated that TNF-α G308A polymorphism may act as a potential candidate biomarker for screening, diagnosis, and treatment of osteoporosis, which will help improve individualized therapy of osteoporosis patients in clinics.

Proinflammatory Cytokine Gene Polymorphisms in Bullous Pemphigoid

Bullous pemphigoid (BP) is a rare autoimmune skin blistering disease, characterized by the presence of autoantibodies against hemidesmosomal autoantigens. Cytokine expression is altered in BP patients, and several of these differently expressed cytokines, including IL-1α, IL-1β, IL-8, and TNF-α, contribute to disease pathogenesis. Since genetic polymorphisms in the genes of these cytokines might be implicated in susceptibility to BP disease, we aimed at testing this implication in susceptibility to BP in an Iranian cohort. Blood samples were collected from the subjects and genomic DNA was extracted. To detect the single nucleotide polymorphisms (SNPs), IL-1α (rs1800587), IL-1β (rs1143627, rs16944, rs1143634), IL-8 (rs4073), and TNF-α (rs1799964, rs1800630, rs1799724, and rs361525) genes were genotyped in BP patients and healthy controls as well as IL-8 (rs4073) in pemphigus vulgaris (PV) patients. Quantitative gene expression was evaluated by RT-PCR analysis. A significant difference was observed in the distribution of genotypes or alleles of IL-8 SNP between the BP patients and controls. The A-allele of IL-8 SNP is significantly more prevalent in the control individuals compared to the BP patient. To further validate this observation, we included PV patients as an additional control. Again, the A-allele of IL-8 SNP is significantly more prevalent in the PV compared to the BP patients. While we observed a trend toward significant differences regarding alleles of TNF-α rs1799724 as well as alleles of TNF-α rs1799964, this difference was, however, not evident after correction for multiple analysis. There was no significant difference in all other studied SNPs. In contrast to IL-1α, IL-1β, and TNF-α, IL-8 gene expression levels were significantly higher in the patients than that of controls. The minor allele in IL-8 SNP might play a protective role in susceptibility to BP in Iranian patients. Although higher expression levels of IL-8 gene was found in the patients compared with healthy controls, these levels, however, suggest no association with the examined polymorphism. Moreover, further investigation revealed an elevation in gene expression between wild and polymorphic genotypes of IL-1α rs1800587 and TNF-α rs361525 in the patient group and these SNPs are therefore associated with altering the levels of gene expression.

Lack of association of -863C/A (rs1800630) polymorphism of tumor necrosis factor-a gene with rheumatoid arthritis

INTRODUCTION

Multifunctional pro-inflammatory cytokine tumor necrosis factor-α (TNF-α) has been implicated in a variety of inflammatory diseases including rheumatoid arthritis (RA). TNF-α polymorphisms are mostly located in its promoter region and play a significant role in disease susceptibility and severity. We therefore sought to investigate TNFA -863C/A (rs1800630) polymorphism association with RA activity in our Pakistani study group.

MATERIAL AND METHODS

A total of 268 human subjects were enrolled. Among them, 134 were RA patients and 134 were controls. In this study the physical parameters of RA patients were collected, and the disease activity was measured by DAS28. The genotypes were determined following the allele-specific PCR along with the pre-requisite internal amplification controls. Subsequently, data were analyzed statistically for any significant association including χ²/Fisher's exact test using GraphPad prism 6 software.

RESULTS

We found that the TNF-α -863 C/A (rs1800630) variant was not differentially segregated between cases and controls in either genotype frequency, with χ² of 2.771 and a p-value of 0.2502, or allele frequency, with χ² of 2.741 and a p-value of 0.0978, with an odds ratio (95% CI) of 0.7490 (0.5317-1.055).

CONCLUSIONS

The lack of positive association of TNF-α -863(rs1800630) polymorphism in our study group implies that TNF-α -863 polymorphism is not a susceptible marker to RA and cannot serve as a genetic factor for screening RA patients in Pakistan. There might be other factors that may influence disease susceptibility. However, further investigations on additional larger and multi-regional population samples are required to determine the consequences of genetic variations for disease prognosis.

Haplotypes of TNFα/β Genes Associated with Sex-Specific Paranoid Schizophrenic Risk in Tunisian Population

Several medical research findings have announced a strong association between the biology of cytokines and various brain activities. Since growing evidences suggest the crucial and complex role of the tumor necrosis factor in the CNS, we have hypothesized that functional genetic variants of the LTA and TNFA genes (LTA +252A/G (rs909253) and TNFA -857C/T (rs1799724) and TNFA -238G/A (rs361525)) may be involved in the predisposition to schizophrenia. This research is based on a case-control study. The RFLP-PCR genotyping was conducted on a Tunisian population composed of 208 patients and 208 controls. We found a strong significant overrepresentation of the minor alleles (G, T, and A, respectively) in all patients compared with controls (p = 0.003, OR = 1.55; p = 0.005, OR = 1.78; and p = 0.0001, OR = 1.74, respectively). This correlation was confirmed for male but not for female patients. Interestingly, the frequencies of the minor alleles were significantly more common among patients with paranoid schizophrenia when compared with controls (p = 0.003, OR = 1.75; p = 5 · 10^-6, OR = 3.04; and p = 4 · 10^-6, OR = 2.35, respectively). This potential association was confirmed by a logistic binary regression analysis only for the development of the paranoid form of schizophrenia (p = 0.001/OR = 2.6; p = 0.0002/OR = 3.2; and p = 0.0004/OR = 3.1, respectively) and remained not significant for the other subtypes. Moreover, our study showed an important association between GCA haplotype and the development of this pathological form (p = 10^-4, OR = 3.71). In conclusion, our results proved a significant association between the three polymorphisms and paranoid schizophrenia, at least in the Tunisian population, suggesting a substantially increased risk for paranoid schizophrenia with dominant inheritance of these three minor alleles.

Polymorphisms and haplotypes in the promoter of the TNF-α gene are associated with disease severity of severe fever with thrombocytopenia syndrome in Chinese Han population

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease that is caused by a novel bunyavirus, SFTSV. We assessed whether the single nucleotide polymorphisms (SNPs) in the tumor necrosis factor-alpha (TNF-α) were associated with risk to severity of SFTS. Five TNF-α SNPs (SNP1: T-1031C; SNP2: C-863A; SNP3: C-857T; SNP4: G-308A; SNP5: G-238A) were genotyped in 987 hospitalized SFTS patients and 633 asymptomatic/mild SFTSV-infected subjects of Chinese Han origin. Multivariate logistic regression analysis was used to calculate adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs). The hospitalized SFTS patients had significantly lower frequency of G-238A A allele than those with mild/asymptomatic infection (P = 0.006). Furthermore, T-1031C C allele (P < 0.001) and G-238A A allele (P < 0.001) were significantly associated with decreased risk of death. Multiple haplotypes were significantly associated with decreased risk of SFTS hospital admission (SNP1-2, CC; SNP1-3, CCC; SNP1-4, CCCG; SNP1-5, CCCGA; SNP2-4, CCGA; SNP3-5, CGA; SNP4-5, GA) and death (SNP1-2, CA; SNP1-3, CAG; SNP1-4, CACG; SNP1-5, CACGG; SNP2-3, AC; SNP2-4, ACG; SNP2-5, ACGG) after correction for multiple comparisons. By using the ELISA assay, we observed that TNF-α concentration of hospitalized patients was significantly increased in acute phase than in convalescent phase (P < 0.001). Elevated TNF-α concentration was also revealed from fatal patients (P < 0.001). The -238A allele was associated with decreased serum TNF-α levels in SFTS patients in acute phase (P = 0.01). Our findings suggest that polymorphisms in TNF-α gene may play a role in mediating the risk to disease severity of SFTS in Chinese Han population.

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease that is caused by a novel bunyavirus. The current study disclosed the single nucleotide polymorphisms (SNPs) in the tumor necrosis factor-alpha (TNF-α) were associated with risk to disease severity of SFTS. These findings suggest that polymorphisms in TNF-α gene may play a role in mediating the risk to disease severity of SFTS in Chinese Han population. The study will be of interest to either the clinicians devoted to the prevention and therapy of SFTS or the geneticists devoted to studying the genetic susceptibility mechanisms of common diseases.

Genetics in TNF-TNFR pathway: A complex network causing spondyloarthritis and conditioning response to anti-TNFα therapy

Objectives

We investigated whether polymorphisms (SNPs) in the promoter region of TNFA, or in the autoinflammatory TNFRSF1A and MEFV genes, concur with HLA-B27 in enhancing the risk of Spondyloarthritis (SpA) and/or in predicting the response to anti-TNFα treatment.

Methods

373 controls and 137 SpA (82 with Psoriatic Arthritis-PsA and 55 with Ankylosing Spondylitis- AS; 98/137 under TNFα inhibitor therapy) from the Veneto Region (Italy) were studied. TNFA polymorphisms (-1031T>C;-857C>T;-376G>A;-308G>A;-238G>A) and HLA-B27 were assayed by RT-PCR. Direct sequencing of MEFV (exons 2,3,5 and 10) and TNFRSF1A (exons 2,3,4 and 6) genes were performed.

Results

HLA-B27 was associated with AS (χ² = 120.1; p = 0.000). Only the TNFA -1031T>C was singly associated with SpA, and the haplotype C/G, resulting from -1031T>C/-308G>A combination, was significantly associated with a reduced risk of SpA (OR: 0.67, CI: 0.46–0.97; p = 0.035). Two SNPs were identified in TNFRSF1A, the R92Q (Minor allele frequency-MAF = 0.034) and c.625+10A>G (MAF = 0.479). None of them was associated with SpA (p>0.05). The TNFRSF1A c.625+10 G allele was associated with late response to anti-TNFα therapy (p = 0.031). Twenty-one SNPs were identified in MEFV gene, 10 with a known potential functional significance. Variant alleles were extremely rare in our population (MAF<0.025) except for R202Q (MAF = 0.27). None was associated with SpA diagnosis (p>0.05).

Conclusion

TNFRSF1A and MEFV gene SNPs are not associated with SpA in the North-East of Italy. AS risk appears to depend not only on HLA-B27, but also on the protective TNFA haplotype -1031C/-308G. The TNFRSF1A c.625+10A>G impacts on the response to anti-TNFα therapy.

Shanghai Health Study (2001-2009): What was learned about benzene health effects?

The Shanghai Health Study (SHS) was a large epidemiology study conducted as a joint effort between the University of Colorado and Fudan University in Shanghai, China. The study was funded by members of the American Petroleum Institute between 2001 and 2009 and was designed to evaluate the human health effects associated with benzene exposure. Two arms of the SHS included: an occupational-based molecular epidemiology study and several hospital-based case control studies. Consistent with historical literature, following sufficient exposure to relatively high airborne concentrations and years of exposure, the SHS concluded that exposure to benzene resulted in an increased risk of various blood and bone marrow abnormalities such as benzene poisoning, aplastic anemia (AA), myelodysplastic syndrome (MDS), and acute myeloid leukemia (AML). Non-Hodgkin lymphoma (NHL) was not significantly increased for the exposures examined in this study. Perhaps the most important contribution of the SHS was furthering our understanding of the mechanism of benzene-induced bone marrow toxicity and the importance of identifying the proper subset of MDS relevant to benzene. Investigators found that benzene-exposed workers exhibited bone marrow morphology consistent with an immune-mediated inflammatory response. Contrary to historic reports, no consistent pattern of cytogenetic abnormalities was identified in these workers. Taken together, findings from SHS provided evidence that the mechanism for benzene-induced bone marrow damage was not initiated by chromosome abnormalities. Instead, chronic inflammation, followed by an immune-mediated response, is likely to play a more significant role in benzene-induced disease initiation and progression than previously thought.

Associations of tumor necrosis factor-α-308 polymorphism with dengue infection: A systematic review and meta-analysis

Inconsistency of reported associations between the tumor necrosis factor-alpha-308 (TNFα-308) polymorphism (rs1800629) and dengue virus infection prompted a meta-analysis, to obtain more precise estimates. A literature search yielded 14 case-control studies. We calculated pooled odds ratios (OR) and 95% confidence intervals in three groups according to severity, dengue fever (DF), dengue hemorrhagic fever (DHF) and dengue (DEN) using standard genetic models. Pooled ORs were subjected to modifier treatment where re-analysis was confined to Hardy-Weinberg compliant (HWC) studies. Heterogeneity of outcomes warranted examining their sources with outlier treatment. In subgroup analysis, we compared Asian and South/Central American (SCA)/Brazilian effects. Overall pooled outcomes yielded no significant effects (OR 0.66-1.44, P=0.08-0.96). In the dominant-codominant model, pooled effects were heterogeneous (I²=47%-71%) which was lost/reduced (I²=0%-43%) when outlier treatment was applied. This also yielded significant associations (OR 0.68-0.77, P=0.02-0.05). Our results are best seen in the Asian subgroup, which in itself already yielded significant effects in DEN (OR 0.62-0.67, P=0.01-0.02). These reduced risk findings were significant from the tests of interaction (P=0.001-0.02) which highlights the protective effects of TNFα-308 among Asians. TNFα-308 effects on dengue are based on significance and non-heterogeneity of the post-outlier outcomes in the dominant and codominant models. Here, pooled effects may also be ethnic specific, where Asians are protected but not SCA. Both modified and Asian effects are up to 38% protective.

Tumor necrosis factor alpha gene polymorphisms and haplotypes in Egyptian children with nephrotic syndrome

BACKGROUND

Nephrotic syndrome (NS) characterized by complex pathogenesis and clinical course with relapses; and needs novel breakthroughs for decades. Polymorphisms of cytokines genes including tumor necrosis factor alpha (TNF-α)may influence susceptibility to NS as well as different patients' steroid responses. In the current study, we demonstrated the potential roles of TNF-α promoter gene polymorphisms [-238, -308, -863] and haplotypes in susceptibility to childhood NS. Also, elucidating their possible influence on patients' steroid response and serum TNF-α level.

METHODS

This case-control study included 150 children suffering from NS and 150 healthy children. Polymerase chain reaction- restriction-fragment length polymorphism (PCR-RFLP) was performed to evaluate different TNF-α gene polymorphism. TNF-α serum levels were assessed by ELISA.

RESULTS

Serum TNF-α levels were significantly higher in NS patients than in controls and in steroid resistant NS (SRNS) than in steroid sensitive NS (SSNS) (P<0.001 for each). The risk of NS in patients carrying TNF-α-238GA genotype, and TNF-α-308GA or AA genotypes and allele A was significantly increased compared to healthy children. While no significant association was detected between TNF-α-863 and NS. The risk of resistance to steroid therapy was significantly high in NS carrying TNF-α-238GA genotype and A allele, TNF-α-308, AA genotypes and A allele, and TNF-α-863CA, AA genotypes and A allele. The TNF-α GCG (-308/-863/-238) haplotype has protective roles against NS and steroid resistance. However, the risk of NS was significantly high in TNF-α AAG and AAA haplotype's carriers compared to healthy children. Additionally the risk of steroid resistance was significantly high in TNF-α AAA haplotype's NS carrier (OR (95%CI): 2.2 (1.19-4.36), P=0.01). Moreover, we found significant higher serum TNF-α levels NS patients including SSNS and SRNS carrying mutant allele TNF-α-238GA genotype, -308GA and AA and -863CA and AA wild genotype's carriers than in those GG, GG and CC respectively. Interstingely, TNF-α levels were significantly higher in healthy children carrying TNF-α(-308/-863/-238) [AAG and AAA haplotypes], NS cases carrying [ACA, AAG, AAA haplotypes], and in SSNS carrying [ACA and AAA haplotypes] than in those carrying GCG, haplotype of wild alleles.

CONCLUSION

This study reported, for the first time, that TNF-α promoter gene polymorphisms and/or haplotypes are risk factors of NS and resistance to steroid among Egyptian children.

Association of tumor necrosis factor-α -308 G/A gene polymorphism with coronary artery diseases: An evidence-based study

BACKGROUND

Coronary artery disease (CAD) is the leading cause of death worldwide and remains a major health problem, providing the rationale for identification of molecular markers for detection of individuals at high risk of developing CAD. Tumor necrosis factor-α (TNF-α) plays a crucial role in the pathogenesis of CAD. We have therefore explored the association of TNF-α 308 (G/A) gene polymorphism in 903 individuals with/without CAD.

METHODS

TNF-α 308 gene polymorphism was analyzed in 903 subjects of whom 222 were healthy controls. Among the 681 patients who were investigated angiographically, 468 had ≧50% stenosis and 213 patients had <50% stenosis. Biochemical profiles (eg, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, fasting blood glucose, and CRP) were evaluated. Associations between TNF-α genotypes with biochemical and anthropometric characteristics were determined.

RESULTS

The frequencies of TNF-α-AA or AG genotypes were significantly lower in patients classified as CAD patients with ≥ or <50% obstruction in at least one coronary artery, compared to the control group. We observed that CAD patients with ≥50% stenosis and with AA genotype were associated with higher risk of CAD with OR of 3.56 (95%CI: 1.02-12.41; P=.046) using multivariate analysis. Moreover, we found that TNF-α-308-AA genotype was associated with blood pressure and CRP level in CAD patients, compared to the wild type-genotype.

CONCLUSION

Our data showed an association of TNF-α-308G/A polymorphism with CAD patients with ≥50% obstruction, supporting the need for further investigations on the role of TNF-α-308G/A polymorphism with hypertension.

Association of TNF-α Gene Polymorphisms with Production of Protein and Susceptibility to Chronic Hepatitis B Infection in the South East Iranian Population

BACKGROUND

The host genetic background regulates the natural history of chronic hepatitis B virus (HBV) infection.

OBJECTIVES

The aim of this study was to investigate the association between TNF-α gene polymorphism in the promoter region and susceptibility to chronic hepatitis B virus infection.

METHODS

Four polymorphisms of TNF-α gene including -238 A/G, -308 A/G, -857 C/T, and -863 A/C were analyzed by PCR-RFLP in 100 chronic HBV infected patients (HBV group), 40 spontaneously recovered HBV subjects (SR group), and 100 healthy controls (C group). Also, serum levels of protein were monitored.

RESULTS

The study showed that the existence of -308 G, -857 C, and -863 A alleles significantly increased susceptibility to chronic HBV infection. In addition, GGCA haplotype had a higher frequency in HBV patients than C and SR groups that might be related to the natural history of the infection. Chronic HBV patients with -308 GG, -857 CC, and -863 AA genotypes had lower serum levels of TNF-α compared to those with other genotypes.

CONCLUSIONS

The results indicated that there was a positive association between susceptibility to chronic HBV infection and TNF-α polymorphism. In addition, HBV patients carrying -308 GG, -857 CC, and -863 AA genotypes with lower serum levels of TNF-α had an increased risk of infection.

Assessment of TNFA polymorphisms at positions -857 and -863 in Polish peptic ulcer patients

PURPOSE

Peptic ulceration connected with chronic inflammation in gastrointestinal mucosa could be induced by Helicobacter pylori infection. Tumor necrosis factor alpha (TNF-α) encoded by TNFA gene is a key mediator in the inflammation process. There are several polymorphisms in the promoter of TNFA influencing its transcriptional activity. -857C>T (rs1799724) and -863C>A (rs1800630) substitutions may be responsible for increased TNFA transcription and TNF-α production. The association of these two polymorphisms with peptic ulceration and the development of H. pylori infection in peptic ulcer patients in Poles were evaluated.

MATERIAL AND METHODS

Polymorphisms were assessed by PCR-RFLP in 203 peptic ulcer patients. H. pylori infection was confirmed by rapid urease test. The results of genotyping were compared with those obtained for 248 healthy Polish individuals.

RESULTS

There were no significant differences in genotype and allele frequencies for both investigated polymorphisms between peptic ulcer patients and healthy individuals. No associations between frequencies of particular genotypes and alleles for both SNPs and the presence of H. pylori infection in peptic ulcer patients and in subgroups of peptic ulcer women and men were confirmed.

CONCLUSIONS

The investigated SNPs are not risk factors for peptic ulcer development. They are not risk factors for H. pylori infection in ulcer patients.

Relationship of bovine TNF-α gene polymorphisms with the risk of bovine tuberculosis in Holstein cattle

Many studies suggest significant genetic variation in the resistance of cattle and humans to infection with Mycobacterium bovis (M. bovis), the causative agent of zoonotic tuberculosis. TNF-α promotes inflammation and induces apoptosis in response to mycobacterial infection. The aim of the present study was to investigate the influence of single nucleotide polymorphisms of the TNF-α gene on bovine tuberculosis (bTB) susceptibility. We genotyped the TNF-α gene in 74 bTB-infected Holstein cows and 90 healthy control animals. The influence in the exon 3 region of TNF-α polymorphisms on bTB susceptibility was subsequently investigated by association analysis. Our finding demonstrated that the g.27534932A>C polymorphism of the TNF-α is associated with bTB in Holstein cattle. The susceptibility of cattle with the g.27534932A>C genotype compared with the CC genotype was 4.11-fold (95% CI, 1.27–13.36; P=0.02) higher. The g.27534932A>C polymorphism located in exon 3 of the TNF-α gene, and the functional consequence was missense. The deduced amino acid sequence for the protein product revealed an arginine to serine conversion at position 159, which may affect initiation of protein synthesis and disrupt normal TNF-α function that protects animals against mycobacterial infection. A significant association was observed with the A allele as a risk factor for bTB susceptibility (OR, 3.84; 95% CI, 1.21–12.17; P=0.02). In conclusion, this is the first report showing that the g.27534932A>C polymorphism may contribute to TNF-α-mediated bTB susceptibility.

TNF-α -238, -308, -863 polymorphisms, and brucellosis infection

BACKGROUND

Brucella abortus is an intracellular bacterium that affects humans and domestic animals. Tumor necrosis factor-alpha (TNF-α) has been shown as a key player in the induction of cell-mediated resistance against Brucella infection. We aimed to evaluate the possible influence of the TNF-α promoter polymorphisms (-308 G/A, -238 G/A, and -863 C/A) on the susceptibility of human brucellosis.

METHODOLOGY

A total of 153 patients with active brucellosis and 128 healthy individuals were recruited. All subjects were genotyped for the polymorphisms in the TNF-α gene by Allele-Specific polymerase chain reaction analysis.

RESULTS

Our results showed that the TNF-α -308 GG genotype was significantly more frequently present in controls than in brucellosis patients (91% vs. 75%), thus was a protective factor against developing brucellosis (OR=0.313, p=0.001). In contrast, the -308 GA genotype (OR=3.026, p=0.002) and minor allele (A) (OR=3.058, p=0.001) as well as AAG haplotype (OR=4.014, p=0.001) conferred an increased risk of brucellosis. However, the -238 G/A and -863 C/A polymorphisms were not associated with the risk of brucellosis at both allelic and genotypic levels (p>0.05).

CONCLUSION

Our study revealed that the TNF-α -308 A allele or GA heterozygosity or AAG haplotype were associated with an increased risk of brucellosis in our population.

Genetic basis of interindividual susceptibility to cancer cachexia: selection of potential candidate gene polymorphisms for association studies

Cancer cachexia is a complex and multifactorial disease. Evolving definitions highlight the fact that a diverse range of biological processes contribute to cancer cachexia. Part of the variation in who will and who will not develop cancer cachexia may be genetically determined. As new definitions, classifications and biological targets continue to evolve, there is a need for reappraisal of the literature for future candidate association studies. This review summarizes genes identified or implicated as well as putative candidate genes contributing to cachexia, identified through diverse technology platforms and model systems to further guide association studies. A systematic search covering 1986-2012 was performed for potential candidate genes / genetic polymorphisms relating to cancer cachexia. All candidate genes were reviewed for functional polymorphisms or clinically significant polymorphisms associated with cachexia using the OMIM and GeneRIF databases. Pathway analysis software was used to reveal possible network associations between genes. Functionality of SNPs/genes was explored based on published literature, algorithms for detecting putative deleterious SNPs and interrogating the database for expression of quantitative trait loci (eQTLs). A total of 154 genes associated with cancer cachexia were identified and explored for functional polymorphisms. Of these 154 genes, 119 had a combined total of 281 polymorphisms with functional and/or clinical significance in terms of cachexia associated with them. Of these, 80 polymorphisms (in 51 genes) were replicated in more than one study with 24 polymorphisms found to influence two or more hallmarks of cachexia (i.e., inflammation, loss of fat mass and/or lean mass and reduced survival). Selection of candidate genes and polymorphisms is a key element of multigene study design. The present study provides a contemporary basis to select genes and/or polymorphisms for further association studies in cancer cachexia, and to develop their potential as susceptibility biomarkers of cachexia.

Does Inflammation Have a Role in the Pathogenesis of Cardiac Syndrome X? A Genetic-Based Clinical Study With Assessment of Multiple Cytokine Levels

We compared Turkish patients with cardiac syndrome X (CSX) and controls with respect to serum pro- and anti-inflammatory cytokine levels, as well as the single-nucleotide polymorphisms located in the promoter regions of their related genes. This study included 111 consecutive patients angiographically diagnosed with CSX and 111 healthy controls with similar demographic characteristics. Serum interleukin (IL) 6, tumor necrosis factor α (TNF-α), and IL-10 levels were measured, and the genotypes of the patients and controls were determined using standard methods. Serum IL-6 and IL-10 levels were significantly higher in the CSX group than in the control group ( P < .01, respectively). Serum TNF-α level was lower in the CSX group than in the control group ( P < .001). On the other hand, participants with CSX and healthy controls were not significantly different with respect to the genotype distributions of IL-6, TNF-α, and IL-10 genes. As a result of our study, both pro-inflammatory and anti-inflammatory cytokines may play a role in the pathogenesis of CSX. In contrast, the studied gene polymorphisms did not influence CSX pathogenesis.

Inflammation and Nutritional Science for Programs/Policies and Interpretation of Research Evidence (INSPIRE)

An increasing recognition has emerged of the complexities of the global health agenda—specifically, the collision of infections and noncommunicable diseases and the dual burden of over- and undernutrition. Of particular practical concern are both 1) the need for a better understanding of the bidirectional relations between nutritional status and the development and function of the immune and inflammatory response and 2) the specific impact of the inflammatory response on the selection, use, and interpretation of nutrient biomarkers. The goal of the Inflammation and Nutritional Science for Programs/Policies and Interpretation of Research Evidence (INSPIRE) is to provide guidance for those users represented by the global food and nutrition enterprise. These include researchers (bench and clinical), clinicians providing care/treatment, those developing and evaluating programs/interventions at scale, and those responsible for generating evidence-based policy. The INSPIRE process included convening 5 thematic working groups (WGs) charged with developing summary reports around the following issues: 1) basic overview of the interactions between nutrition, immune function, and the inflammatory response; 2) examination of the evidence regarding the impact of nutrition on immune function and inflammation; 3) evaluation of the impact of inflammation and clinical conditions (acute and chronic) on nutrition; 4) examination of existing and potential new approaches to account for the impact of inflammation on biomarker interpretation and use; and 5) the presentation of new approaches to the study of these relations. Each WG was tasked with synthesizing a summary of the evidence for each of these topics and delineating the remaining gaps in our knowledge. This review consists of a summary of the INSPIRE workshop and the WG deliberations.

Genetic disposition and modifiable factors independently associated with anemia in patients with type 2 diabetes mellitus

AIMS

Anemia is prevalent but under-recognized in patients with diabetes mellitus (DM). Genetic variants in angiotensin-converting enzyme (ACE), tumor necrosis factor-alpha (TNF-α) and erythropoietin (EPO) have been associated with diabetic nephropathy. In the present study, we investigated the associations between anemia and polymorphisms in EPO promoter (rs1617640), TNF-α G-308A and ACE Insertion/Deletion in Chinese patients with type 2 diabetes.

METHODS

Polymorphisms in ACE, TNF-α and EPO were genotyped in 1142 patients. Anemia was defined as hemoglobin (Hb) levels below 12 g/dL for women and 13 g/dL for men.

RESULTS

286 (25%) patients had anemia. Patients with anemia were older, had longer duration of diabetes, worse renal function and more albuminuria. ACE Insertion/Deletion and TNF-a G-308A were not associated with anemia. The frequencies of EPO polymorphism (rs1617640) were significantly different between anemic and nonanemic patients. Patients with TT genotype had higher prevalence of anemia than those with TG and GG. Regression analysis identified EPO SNP, duration of DM, serum albumin, albuminuria and renal function independently associated with anemia. After adjusting for multiple variables, TT and TG genotypes were associated with 3-5-fold increased risk for anemia compared to GG.

CONCLUSIONS

The EPO genotype in Chinese patients with type 2 diabetes is associated with anemia and may help to identify those at risk. Further evaluation of its effect on clinical outcomes in prospective studies may be useful to predict the outcomes of erythropoiesis stimulating therapy, and to individualize anemia management.

Association of tumor necrosis factor (TNF) promoter polymorphisms with plasma TNF-α levels and susceptibility to diabetic nephropathy in North Indian population

AIM

The concept of diabetic nephropathy (DN) as a metabolic disease is now being replaced by chronic low-grade inflammatory disease. Tumor necrosis factor-alpha (TNF-α) is a proinflammatory cytokine which plays an important role in the pathogenesis and clinical outcome of DN. Therefore, this work was planned to evaluate the association of -863C/A (rs1800630) and -1031T/C (rs1799964) polymorphisms in TNF gene with plasma TNF-α levels and DN among subjects with type 2 diabetes (T2DM) in a population from North India.

METHODS

Age and sex matched 100 healthy controls (HC), 100 T2DM subjects without nephropathy (DM) and 100 subjects with DN were screened for above polymorphisms using the PCR-RFLP methods. Plasma TNF-α levels were measured by ELISA. Analysis of variance and logistic regression were used to associate individual polymorphisms with plasma TNF-α levels and DN.

RESULTS

The allelic frequencies of -863C/A were 0.86/0.14 in HC, 0.72/0.23 in DM and 0.84/0.16 in DN, and that of -1031T/C were 0.89/0.11 in HC, 0.95/0.05 in DM and 0.80/0.20 in DN. The carriers of -863A allele had significantly lower plasma TNF-α levels (p<0.05). The -863C/A (OR=0.439, 95% CI=0.244-0.789, p=0.006) and -1031T/C (OR=3.0, 95% CI=1.355-6.642, p=0.007) were strongly associated with risk of development of DN.

CONCLUSIONS

-863C/A was associated with low whereas -1031T/C with high TNF-α levels. The, results suggest that -863C/A polymorphism might be protective whereas -1031T/C may be associated with increased risk for DN in subjects with T2DM from North India.

Maternal risk for down syndrome and polymorphisms in the promoter region of the DNMT3B gene: a case-control study

BACKGROUND

Epigenetic changes leading to improper methylation of the pericentromeric region of chromosome 21 may contribute to the nondisjunction of this chromosome. Polymorphisms in the DNA Methyltransferase 3B (DNMT3B) gene, one of the crucial gene of the folate metabolism, affects the activity of the enzyme and increases the susceptibility of nondisjunction in mothers of Down syndrome children (MDS).

METHODS

Considering this hypothesis we investigated the association of single nucleotide polymorphisms in the promoter region of the DNMT3B gene (rs1569686 -579G>T; rs2424913 -149C>T) with a predisposition of mothers to deliver a Down syndrome (DS) child. The study was performed on DNA samples from 150 MDS and 172 control mothers. Transmission disequilibrium tests were performed on 103 DS trio families. Genotyping was done using a polymerase chain reaction-restriction fragment length polymorphism method.

RESULTS

With respect to the single nucleotide polymorphisms studied, no significant difference was observed in the genotypes and alleles frequency distributions between MDS and control mothers. The frequency of the DNMT3B-579G allele was, respectively, 0.34 in MDS and 0.33 in control mothers whereas the frequency of the DNMT3B-149C allele was respectively 0.31 in MDS and 0.26 in control mothers. No significant deviation in genotypic combinations as well as in transmission disequilibrium tests analysis was observed. However, a strong linkage disequilibrium was observed with significant differences in the distribution of G-T and G-C haplotypes among case and control mothers.

CONCLUSION

Although the above studied polymorphisms of DNMT3B may not be an independent risk factor it might be possible that certain allelic combinations (G-T) are. This finding suggests that DNMT3B might be a maternal risk factor for DS in our Indian cohort. Replication studies are required to confirm these findings.

Association of TNF -1031 C/C as a potential protection marker for leprosy development in Amazonas state patients, Brazil

Polymorphisms present in the TNF promoter region has shown to influence the gene transcription. Leprosy displays different clinical manifestations according to the immune responses of the individual infected with Mycobacterium leprae. In this study, we evaluated the single nucleotide polymorphisms (SNPs) -238 G/A (rs361525), -308 G/A (rs1800629), -857 C/T (rs1799724), -863 A/C (rs1800630) and -1031 T/C (rs1799964) in the promoter region of the TNF to see whether these SNPs influence host-susceptibility to leprosy and the different clinical manifestation. Nucleotide sequencing was performed with DNA samples from 108 leprosy patients and 253 control subjects. An association between -1031 C/C genotype and protection from leprosy was observed when leprosy patients were compared to controls (OR 0.11; 95% CI=0.01-0.82; p=0.012). The -857 C/T genotype may be associated with susceptibility to leprosy (OR=1.81; 95% CI=1.09-3.00; p=0.028). Similar genotype and allele frequencies for the SNPs -308 G/A and -238 G/A were observed between leprosy patients and control subjects. Altogether, TNF polymorphisms in the promoter region may be predictive of leprosy outcome.

Investigation of -308G>A and -1031T>C polymorphisms in the TNFA promoter region in Polish peptic ulcer patients

BACKGROUND/AIMS

Tumor necrosis factor α (TNF-α) encoded by TNFA is a key mediator in inflammation, a precursor condition for peptic ulceration. Promoter polymorphisms of TNFA that influence its transcriptional activity and TNF-α production are known. TNFA-308G>A (rs1800629) and TNFA-1031T>C (rs1799964), which are responsible for increased TNFA transcription, could influence the risk of peptic ulceration. This study aimed to investigate these polymorphisms and to evaluate their association with peptic ulcer disease and Helicobacter pylori infection in the Polish population.

METHODS

Gastric mucosa specimens obtained from 177 Polish peptic ulcer patients were used to conduct rapid urease tests and to assess the investigated polymorphisms by polymerase chain reaction-restriction fragment length polymorphism. Genotyping data were compared with the results obtained from healthy individuals of Polish origin.

RESULTS

There were no significant differences in genotype and allele frequency of the investigated polymorphisms between peptic ulcer patients and healthy individuals. No associations between the frequencies of particular genotypes and alleles for both single-nucleotide polymorphisms (SNPs) and the presence of H. pylori infection in peptic ulcer patients and in subgroups of men and women with peptic ulcer disease were found.

CONCLUSIONS

The investigated SNPs are not risk factors for either peptic ulcer or H. pylori infection development in the Polish population. The results require verification in a larger cohort.

IFN-gamma and TNF associated with severe falciparum malaria infection in Saudi pregnant women

Background

Tumour necrosis factor (TNF) and interferon gamma (IFN-γ), encoded by TNF-836 C/A (rs 1800630) and IFN-γ -1616 C/T (rs2069705) genes, are key immunological mediators that are believed to both play protective and pathological roles in malaria. The aim of this study was to investigate the relationship between TNF-836 C/A and IFN-γ-1616 C/T polymorphism and susceptibility to severe malaria in pregnant women.

Methods

A prospective cohort (cross-sectional) study was conducted in pregnant women attending the out-patient clinic in King Fahad Specialist Hospital in Jazan (KFSHJ), with a clinical diagnosis of malaria. A total of one hundred and eighty six pregnant women were genotyped for single nucleotide polymorphism (SNP) for TNF and IFN-γ using Taqman® MGB Probes. Serum cytokine concentrations were measured by sandwich ELISA method.

Results

A hospital case–control study of severe malaria in a Saudi population identified strong associations with individual single-nucleotide polymorphisms in the TNF and IFN-γ genes, and defined TNF-836 C and IFN-γ-1616 T genotypes and alleles which were statistically significantly associated with severe malaria infection. Furthermore, TNF-836 CC and IFN-γ-1616 TT genotypes were associated with higher serum concentration of TNF and IFN-γ, respectively, and with susceptibility to severe malaria.

Conclusions

This data provides a starting point for functional and genetic analysis of the TNF and IFN-γ genomic region in malaria infection affecting Saudi populations.

TNF-α gene promoter polymorphisms contribute to periodontitis susceptibility: evidence from 46 studies

AIM

Tumour necrosis factor-alpha (TNF-α) plays a critical role in the pathogenesis of periodontal disease. TNF-α gene polymorphisms can influence the TNF-α production. Many studies have focused the association between TNF-α gene promoter polymorphisms and periodontitis risk, but these results are still controversial.

MATERIALS AND METHODS

A meta-analysis was performed to assess the effect of TNF-α -308G/A (rs1800629), -238G/A (rs361525) and -863C/A (rs1800630) polymorphisms on either chronic (CP) or aggressive periodontitis (AgP) risk. Odds ratios (ORs) along with their 95% confidence intervals (CIs) were calculated to assess the strength of the association. Forty-six studies involving 5186 cases and 6683 controls were retrieved and analyzed.

RESULTS

The TNF-α -308G/A AA genotype was associated with increased CP risk in Asians, non-smoking Asians and Caucasians, and this polymorphism was significantly associated with elevated risk of AgP in Asians and Caucasians. Asian individuals carrying AA genotype had a significantly increased risk for -863C/A. No significant association was identified between TNF -238G/A polymorphism and CP.

CONCLUSIONS

These findings supported that TNF-α -308G/A and -863C/A polymorphisms may contribute to the susceptibility of periodontitis.

Cure rate of Helicobacter pylori infection in Egyptian children related to CYP2C19 gene polymorphism

OBJECTIVES

This study was done in order to investigate the effect of CYP2C19 genetic polymorphism on the cure rate of children who received proton pump inhibitors (PPI)-based triple therapy for treating Helicobacter pylori (H. pylori) infection.

METHODS

Participants included 100 children with H. pylori-positive gastritis diagnosed by endoscopy and biopsy in addition to H. pylori stool antigen test. Cure rate was assessed after 1 month of completion of a triple treatment course for 14 days. CYP2C19 polymorphism was analyzed by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method.

RESULTS

Results showed that cases with a CYP2C19 genotypic status consistent with the heterozygote extensive metabolizers (HetEMs) had a higher cure rate of H. pylori when compared with the homozygote extensive metabolizers (HomEMs) although it was statistically nonsignificant (84.6 vs. 69.2). In addition, the poor metabolizers (PMs) had a higher cure rate compared with those of the HomEMs which was also statistically nonsignificant (77.8 vs. 69.2). The cure rate was also higher among both the groups of HetEMs and PMs combined together compared to the HomEMs (OR = 2.15, p > 0.05). Comparing cases regarding their age, gender, and severity of H. pylori gastritis revealed a better cure rate in the age group >10 years, in females and in mild and moderate cases than other cases although statistically nonsignificant.

CONCLUSION

The higher cure rate of H. pylori infection using the triple therapy for 2 weeks among HetEMs and PMs cases compared to the HomEMs might warrant a need for a therapy augmentation or modification for the HomEMs.

Genetic polymorphism of DNA methyltransferase 3B 149 C>T and risk of colorectal cancer: a meta-analysis

Numerous studies have investigated the risk of colorectal cancer (CRC) associated with the polymorphism of DNA methyltransferase 3B (DNMT3B) 149 C>T, but results have been inconsistent. We performed this meta-analysis to drive a more precise estimation of the association between this polymorphism and risk of CRC. A comprehensive search was conducted to identify all case-control studies of the -149C>T polymorphism of DNMT3B and CRC risk. A total of seven eligible studies, including 2,666 cases and 4,022 controls, relating the DNMT3B polymorphism of -149C>T to the risk of CRC were identified. It suggested no significant associations between -149C>T polymorphism of DNMT3B gene and the risk of developing CRC in the recessive, dominant, and co-dominant models (for CC versus TT: OR = 0.90, 95% CI = 0.90-1.25, P heterogeneity = 0.37; for recessive model: OR = 0.54, 95% CI = 0.28-1.04, P heterogeneity = 0.00001; for dominant model: OR = 1.07, 95% CI = 0.93-1.23, P heterogeneity = 0.83; and for C allele versus T allele: OR = 0.70, 95% CI = 0.43-1.13, P heterogeneity = 0.00001). In the subgroup analysis, there is no significant associations were also found in European populations (for CC versus TT: OR = 1.09, 95% CI = 0.92-1.30, P heterogeneity = 0.88; for recessive model: OR = 1.00, 95% CI = 0.88-1.13, P heterogeneity = 0.14; for dominant model: OR = 1.50, 95% CI = 0.89-2.54, P heterogeneity = 0.00001; and for C allele versus T allele: OR = 0.70, 95% CI = 0.38-1.28, P heterogeneity = 0.00001). In conclusion, no significant association was found between the -149C>T polymorphisms in DNMT3B and CRC susceptibility.

Tumor necrosis factor-alpha gene promoter region polymorphism and the risk of coronary heart disease

BACKGROUND

Tumor necrosis factor-alpha (TNF- α ) gene polymorphisms have been implicated in the manifestation of atherosclerosis. Controversy exists regarding the link between the cytokine's variant genotype and CHD among different ethnic groups. There have been fewer studies on the TNF- α gene -1031T>C and -863C>A polymorphisms in relation to CHD. Therefore, the current study was designed to investigate the association of the TNF- α gene -1031T>C and -863C>A polymorphisms with CHD in a Pakistani population.

METHODS

Patients with CHD (n = 310) and healthy individuals (n = 310) were enrolled in this study. Genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

RESULTS

A significant difference was observed in the -863C>A polymorphism between patients with CHD and control subjects (P < 0.0001). CHD risk was positively associated with the variant allele -863A (P < 0.0001) in the study subjects. There was no significant link between the -1031T>C polymorphism and CHD risk in the study population. Haplotypes A-T and A-C of the TNF-alpha gene loci at -863 and -1031 showed higher frequency in the patient group compared with controls (P < 0.05).

CONCLUSION

The TNF- α   -863C>A gene polymorphism was associated with the pathogenesis of CHD while the -1031T>C polymorphism did not show any link with the disease in a Pakistani population.

TNF-α haplotype association with polycystic ovary syndrome - a South Indian study

BACKGROUND

Tumor Necrosis Factor Alpha (TNF-α), is a proinflammatory cytokine in the pathogenesis of Polycystic Ovary Syndrome (PCOS). In order to investigate the role of rs1800629 and rs1799964 polymorphisms in relation to anthropometric measures, family history of complex diseases, diet and clinical features, we performed a case control study in PCOS women from South India.

METHODS

A total of 589 samples comprising of 283 patients and 306 controls were enrolled in the present study. Patients were selected based on Rotterdam criteria and ultrasound scanned normal women were selected as controls. Following extraction of DNA, genotyping for rs1800629 and rs1799964 was performed by polymerase chain reaction using tetra primers and PCR-RFLP respectively.

RESULTS

The distribution of genotypes for rs1799964 was significantly different between the groups (p = 0.001), however it was not for rs1800629. Haplotype analysis revealed a significant difference between patients and controls. The predisposing and protective role of haplotype with mutant allele at both loci (combination 3) and haplotype with mutant allele at either loci was reflected by the over representation of combination 3 in patients and combination 2 in controls respectively. In addition, rs1799964 showed an association with dietary habit, clinical hyperandrogenism and AAO. The modifying role of TT genotype on age at onset was noted in quartile analysis.

CONCLUSION

Replicative studies on the influence of TNF-α polymorphism in different ethnic groups may identify the potentiality of these polymorphisms as markers of inflammation and in turn may help the clinicians for the better management of the condition.

Tumor necrosis factor-α (TNF-α) -863C/A promoter polymorphism is associated with type 2 diabetes in Tunisian population

AIMS

Tumor necrosis factor α (TNFα) plays a key role in orchestrating the complex events involved in inflammation and immunity. Accordingly, TNF α has been implicated in a wide range of autoimmune and infectious diseases, but also in conditions such as obesity and insulin resistance. The aim of the present study was to investigate the association between the -863C/A polymorphism in the promoter of the TNFα gene and type 2 diabetes in the Tunisian population.

METHODS

The polymorphism -863C/A in the TNFα gene was determined in 211 type 2 diabetes patients and 345 healthy controls using the Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) analysis.

RESULTS

A significant difference in genotype distribution and allele frequency was observed between patients and controls. Patients with type 2 diabetes had significantly higher frequency of the CA+AA genotypes compared to controls [35.5% vs. 22.3%; OR (95%CI), 1.91 (1.31-2.8); p=0.001]. The type 2 diabetes patient group showed a significant higher frequency of the A allele compared to the controls (0.19 vs. 0.11; p=0.001). After adjustment by a stepwise logistic regression method, hypertension, dyslipidemia, and CA+AA genotype were found to be significantly associated with T2D.

CONCLUSION

The present study showed a significant and independent association between the -863C/A polymorphism of the TNFα gene and type 2 diabetes in the Tunisian population.