TNF-α G-308A Research Articles

Cytokine Status of Serum in Ovarian Cancer Patients with Different Tumor Neoadjuvant Chemotherapy Response.

Polychemotherapy in ovarian cancer (OC) is the second major component of treatment. However, treatment with cytostatics is stopped in 25% of cases because of significant side effects. It is shown that concentration of certain cytokines and their balance is largely formed in accordance with a genetic polymorphism. The objective of the study was to evaluate the cytokine status of blood serum of patients with ovarian cancer with different tumor response to neoadjuvant chemotherapy (NACT). Patients received 2 courses NACT according to the scheme AP. The levels of IL-1β and IL-1Ra, IL-10, TNF-α in blood serum were determined by solid phase ELISA. For molecular genetic studies we selected polymorphic variants in the promoters of the gene represented in dbS`NP NCBI and SNP500 Cancer databases. The sharply declined in patients with ovarian cancer compared with the normal, level of IL-1β correlates with increased levels of IL-1RA. It is found that 75% of patients who had progression of the disease after NACT bear CT genotype of gene IL-1β associated with a low expression of the cytokine, while the TT genotype, providing a high level of the expression of IL-1β gene had met only 25% among patients in this group. At the same time 70% of patients with a complete response are the carriers of the T allele, while a complete response was associated with a higher level of IL-1β than in the progression group. Low secretion of TNF-α in all types of tumor response when testing TNF-α G-308A gene polymorphisms was associated with carriage of GA and AA genotypes, which are associated with low production of this cytokine. Increased compared to the control IL-10 production in patients with ovarian cancer associated with genotype replacement at position 1082 G/A IL-10 gene, which occured in 10% of patients with a complete response and 25% of patients with tumor progression after NACT. All the studied polymorphisms of IL-1β, IL-10 and TNF-α genes in patients with OC are associated with the level of these cytokines and tumor NACT response.

TNFα gene polymorphism in steroid resistant nephrotic syndrome

Cytokines play a main role as progressive factors in nephrotic syndrome (NS). Tumor necrosis factor alpha (TNFα) produced by activated macrophages is often accompanied by pro inflammatory properties. Some cytokine gene polymorphisms like TNFα have associated with various inflammatory diseases as glomerulonephritis. The aim of the current work was to investigate the serum level of TNFα and the association between TNFα G308A polymorphism and the response to steroid therapy in nephrotic syndrome. This study was conducted on 250 subjects, 100 healthy children, 50 steroid sensitive nephrotic syndrome (SSNS), and 100 steroid resistant nephrotic syndrome patients (SRNS). Serum concentration of TNFα was measured by enzyme-linked immunosorbent assay (ELISA) technique and TNFα-G308A gene polymorphism was estimated by polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP). Serum concentrations of TNFα significantly increased in SRNS cases when compared to SSNS subgroups. TNF GA, AA, GA + AA genotypes and A allele showed significant association with risk of NS development within healthy control subjects. TNFα-G308A genotypes and alleles did not differ significantly between SSNS and SRNS groups.

Association of tumor necrosis factor-α (G-308A) genetic variant with matrix metalloproteinase-9 activity and joint destruction in early rheumatoid arthritis.

Matrix metalloproteinases (MMPs) are the key enzymes responsible for the joint destruction. Their activity is regulated by the level of proinflammatory cytokines. The aim of this study was to examine the impact of TNF-α G-308A polymorphism on MMP-9 levels in blood plasma (BP) and synovial fluid (SF) of patients with rheumatoid arthritis (RA) and their role in progression of joint destruction. One hundred thirty-four subjects were enrolled in this study. TNF-α G-308A polymorphism was determined using PCR-RFLP method. ELISA assay was used for the detection of MMP-9 activity in BP and SF. Joint damage was estimated by hands and feet radiography. Larsen score and annual changes in LS were used for quantitative evaluation of joint destruction and radiographic progression of disease. MMP-9 activity in BP and SF was significantly higher in RA compared to controls, as well as in SF of patients with erosive compared to nonerosive RA. Faster radiographic progression and increased MMP-9 activity in BP and SF were detected in the group A (GA or AA genotype carriers) compared to the group G (GG genotype carriers). However, statistical significance was revealed only for MMP-9 activity in SF (p<0.05). MMP-9 activity in BP and SF is significantly higher in RA patients compared to patients with osteoarthritis. The presence of TNF-α-308A allele is associated with increased MMP-9 activity in SF of patients with early RA and may be a predictor of rapid radiographic progression of disease.

Inter-Ethnic Variations in Association of TNF-Alpha G308a Single Nucleotide Polymorphism with Type 2 Diabetes Mellitus - A Review

According to World Health Organization, the prevalence of diabetes mellitus (DM) is on the rise. Tissue necrosis factor- alpha (TNF-α) is one of the inflammatory markers which play role in the pathogenesis of DM. Single nucleotide polymorphism (SNP) at 308G/A has been reported to be associated with type 2 DM. Frequency of TNF-α G308A polymorphism was determined in different ethnic groups and is found to be highly variable. Limited number of studies reported a positive association between type 2 DM and TNF-α SNP and many studies; including meta-analyses failed to find such association. TNF-α G308A polymorphism has been found to be associated with insulin resistance and BMI, although these findings are challenged by many studies. The probable explanation of higher BMI is the association of presence of TNF- α G308A polymorphism with higher rates of lipid synthesis, and suppression of FFA levels in obese persons. There is no single explanation for such highly variable results in different ethnic groups. Presence of yet unidentified gene polymorphism in linkage disequilibrium with TNF-α gene polymorphism could be responsible. The different results can also be contributed to the fact that the study groups differ in age, gender distribution, age of onset of disease, life style, degree of obesity and glucose tolerance. Comprehensive genetic studies of whole TNF-alpha promoter area are required to be done in large population samples in different ethnic groups. Polymorphisms are usually co-related in a complex manner and are co-inherited and conclusions are difficult to be drawn on small sample size.

Effect of cytokine genes and season of birth on personality

To evaluate the interaction effects of season of birth and immune system genes on the personality traits 'Novelty seeking' (NS) and 'Self-directedness' (SD). Based on results on an influence of the immune system on the brain processes, the authors hypothesized that the interaction of immune system genes and season of birth, which is relevant for immune phenotype, can contribute to the development of personality traits. NS and SD were measured in 336 healthy volunteers, aged from 16 to 67 years, using the Temperament and Character Inventory (TCI-125). IL1B C3954T, IL4 C-589T, IL13 C1112T and TNFA G-308A polymorphisms were genotyped. An interaction effect of IL4 C-589T and season of birth on the personality traits was found (F2,322=6.03, pcorr=0.011, η2=0.04). Carriers of the minor allele T, who were born in winter, had lower NS and higher SD. There was a nominal main effect of genotype on SD (F=5.44, p=0.020) as well, with higher SD scores in carriers of the allele T compared to the CC genotype. The results suggest that the etiology of personality and immune characteristics can share common genetic elements including IL-4.

Genetic Contributions to Childhood Obesity: Association of Candidate Gene Polymorphisms and Overweight/Obesity in Korean Preschool Children.

This study was aimed to investigate the association of candidate gene polymorphisms and obesity or overweight in young Korean children. A total of 190 Korean preschool children (96 control, 48 overweight, and 46 obese children) were genotyped for the angiotensin converting enzyme (ACE) insertion (I)/deletion (D), angiotensin II type 2 receptor (AT2) C3123A, transforming growth factor (TGF)-β1 T869C, vascular endothelial growth factor (VEGF) T460C, and tumor necrosis factor (TNF)-α G308A polymorphisms. No differences were found among the groups with respect to age, sex, birth weight, blood pressure levels, and serum concentrations of glucose and total cholesterol. Obese children showed a higher incidence of ACE DD genotype and D allelic frequency compared to the controls (odds ratio [OR], 2.7, 95% confidence interval [CI], 1.01–7.21; OR, 2.5, 95% CI, 1.49–4.19; all P < 0.05). The frequency of TC genotype and C allele in the TGF-β1 T869C polymorphism (OR, 2.08, 95% CI, 1.01–4.27; OR, 1.93, 95% CI, 1.15–3.21) and that in the VEGF T460C polymorphism (OR, 2.5, 95% CI, 1.19–5.28; OR, 2.15, 95% CI, 1.26–3.68) was also higher in obese children than in control subjects (all P < 0.05). Overweight children exhibited a higher frequency of the A allele in the AT2 C3123A polymorphism compared to the controls (OR, 1.72, 95% CI, 1.03–2.88, P < 0.05). There were no differences in the TNF-α G308A polymorphism among the groups. The ACE I/D, AT2 C3123A, TGF-β1 T869C, and VEGF T460C polymorphisms can affect susceptibility to obesity or overweight in Korean children.

Three polymorphisms of tumor necrosis factor-alpha and hepatitis B virus related hepatocellular carcinoma: A meta-analysis.

To assess the association between tumor necrosis factor-alpha (TNF-α) G308A, G238A and C863T polymorphisms and hepatitis B virus related hepatocellular carcinoma (HBV-HCC) susceptibility. We interrogated the databases of Pubmed, Sciencedirect and Viley online library up to March 8, 2016. Odds ratios (ORs) and corresponding 95% confidence intervals (95%CIs) were calculated in a fixed-effects model or a random-effects model when appropriate. In total, 12 case-control studies which containing 1580 HBV-HCC cases, 2033 HBV carrier controls, 395 HBV spontaneously recovered (SR) controls and 1116 healthy controls were included. Compared with GG genotype, the genotypes GA/AA of G308A were associated with a significantly increased HBV-HCC risk when the controls were all healthy individuals (AA vs. GG, OR 2.483, 95%CI 1.243 to 4.959; GA vs. GG, OR 1.383, 95%CI 1.028 to 1.860; GA/AA vs. GG, OR 1.381, 95%CI 1.048 to 1.820). Meanwhile, only the AA vs. GG model of G238A and HBV-HCC showed a statistic significance when the controls were healthy individuals (OR 4.776, 95%CI 1.280 to 17.819). CT genotype of TNF-α C863T could increase HBV-HCC risk whenever the controls were healthy individuals, HBV carriers or HBV recovers. This meta-analysis shows that AA genotype in TNF-α G308A and TNF-α G238A and CT genotype in TNF-α C863T may increase HBV-HCC risk. Therefore, HBV infection seemed to be a more important factor for tumorigenesis of HCC than genetic predisposition in G308A of TNF-α, and interaction between TNF-α C863T polymorphisms and HBV infection might be associated with increased HCC risk.

Gene polymorphism and levels of pro-inflammatory cytokines in plasma and synovial fluid of patients with posttraumatic knee osteoarthritis

Posttraumatic knee osteoarthritis patients (n = 117) and healthy individuals (n = 94) were investigated to determine the genotype and allelic frequency distribution of polymorphic loci Т-31С, С + 3953Т IL-1β and G-308A TNF-α. The plasma and synovial fluid levels of proinflammatory cytokines IL-1β and TNF-α were also measured in 31 patients. The study demonstrated that the plasma and synovial fluid levels of IL-1β but not TNF-α were increased in patients with posttraumatic knee osteoarthritis. Also, the linkage between TNF-α levels and polymorphic locus G-308A TNF-α was shown: the presence of allele–308А was associated with decreased TNF-α levels. It was found that polymorphic loci Т-31С, С+3953Т IL-1β, and G-308A TNF-α are not markers of predisposition to posttraumatic knee osteoarthritis in Russian population of Rostov Oblast.

Association of longevity with TNF-α G308A and IL-6 G174C polymorphic inflammatory biomarkers in Caucasians: a meta-analysis.

Mutations in genes encoding tumor necrosis factor (TNF)-α and interleukin (IL)-6 were previously shown to affect mortality. Single nucleotide polymorphisms (SNPs) in the functional promoter regions of TNF-α (G308A) and IL-6 (G174C) are among the most widely studied. To determine whether TNF-α G308A and IL-6 G174C SNPs confer susceptibility to longevity, we performed a meta-analysis to comprehensively estimate the association between these SNPs and longevity in long-lived individuals (LLI, aged ≥ 80 years). Studies addressing the role of TNF-α and IL-6 SNPs in longevity were identified from the PubMed database. Pooled ORs with 95 % confidence intervals (CIs) were used to assess the association between SNPs and longevity. The meta-analysis was based on four studies of TNF-α G308A and nine of IL-6 G174C, covering a total of 2945 LLI individuals and 2992 controls. Overall, no significantly increased risks were observed for G308A [A vs. G (additive model): OR = 0.98, 95 % CI = 0.79-1.22, p = 0.852; AA + AG vs. GG (dominant model): OR = 0.97, 95 % CI = 0.75-1.24, p = 0.791] or for G174C [C vs. G (additive model): OR = 1.07, 95 % CI = 0.94-1.22, p = 0.293; CC + CG vs. GG (dominant model): OR = 1.09, 95 % CI = 0.93-1.28, p = 0.299]. There was no change in the significance when a cutoff age of ≥ 90 years was introduced. We found no evidence that the TNF-α G308A and IL-6 G174C SNPs affected the probability of reaching an advanced age in Caucasians, and that they have little effect on delaying the onset and progression of age-related diseases, but this does not rule out the possibility of population-specific effects caused by different genes and/or environmental factors and their interactions.

Tumor necrosis factor-α G-308A (rs1800629) polymorphism and aggressive periodontitis susceptibility: a meta-analysis of 16 case-control studies.

Association between tumor necrosis factor-α (TNF-α) G-308A (rs1800629) polymorphism and susceptibility to aggressive periodontitis (AgP) were inconsistent, hence we performed this meta-analysis to clarify the association between them using Comprehensive Meta-Analysis v2.2 software. 16 case-control studies were searched from the PubMed, Embase and CNKI databases up to February 2, 2015. The meta-analysis showed a significantly increased risk in A vs. G (OR = 1.23, 95%CI = 1.04–1.44), AA vs. GG (OR = 2.07, 95%CI = 1.11–3.87), and AA vs. AG+GG genetic models (OR = 2.09, 95%CI = 1.13–3.86); however, the non-significantly increased risk was shown in AG vs. GG (OR = 1.06, 95%CI = 0.85–1.32) and AA+AG vs. GG genetic models (OR = 1.06, 95%CI = 0.85–1.31). Cumulative analysis showed that the association changed from non-significant to significant with new studies accumulated and the CIs became more and more narrow, sensitivity analysis indicated results were statistically robust. Stratified analyses of confirmed of HWE, Asians, Caucasians, and population-based controls obtained results similar to that of overall analysis. There was no evidence of publication bias. In summary, current evidence demonstrates that TNF-a G-308A polymorphism might be associated with AgP susceptibility, especially in Asians and Caucasians.

A study of the effect of the genes of inflammatory proteins on basic personality dimensions

The present research examines the association between two basic dimensions of personality and genes of inflammatory cytokines and mediators reported to be elevated in schizophrenia and affective disorders. Genes of interleukin-1B (IL-1B), interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), C-reactive protein (CRP) and alpha 1-antitrypsin (A1AT) were studied. A total of 639 healthy subjects, aged from 17 to 69 years, participated in the study. The following polymorphisms were genotyped: IL-1B С-511Т (rs16944) and С3954Т (rs1143634), IL-6 G-174C (rs1800795), TNF-α G-308A (rs1800629), CRP (rs279452), A1AT 374G/A (rs709932). Basic personality dimensions Extraversion and Neuroticism were assessed using the Eysenck Personality Inventory. The levels of Extraversion and Neuroticism were not associated with IL-1B, IL-6, TNF-α G and CRP polymorphisms. The association between the A1AT 374G/A polymorphism and Extraversion (р=0.036) was shown. There was a trend towards the association between the A1AT 374G/A polymorphism and Neuroticism (p=0,05) in women. Because this is the first study of the effect of IL-1B, IL-6, TNF-α and A1AT on personality dimensions, the results should be considered as preliminary and need to be replicated.

Is there any increased risk of hypertension, diabetes and cardiac diseases in psoriatic patients with TNF-α G238A and G308A polymorphism?

IntroductionPsoriasis is regarded as a complex autoimmune disease with strong genetic background. Psoriatic patients suffer from many comorbidities including hypertension, diabetes and cardiovascular diseases. Cytokines such as tumor necrosis factor α (TNF-α) may be a key player that triggers psoriasis and diabetes, hypertension and cardiac disease at the same time.AimTo evaluate genetic variations in the TNF-α region and its association with psoriasis and related comorbidities.Material and methodsThe study covered 129 psoriasis patients with three main subgroups with coronary artery disease (n = 41), hypertension (n = 35), and diabetes (n = 21). DNA samples were genotyped for TNF-α G308A and G238A polymorphisms by real-time polymerase chain reaction melting-curve analysis and results were compared statistically.ResultsPsoriatic patients with both TNF-α-298 and TNF-α-308 polymorphisms showed no statistically significant increase in the risk of hypertension (OR = 0.425, χ² = 1.76, p = 0.18 and OR = 1.87, χ² = 1.33, p = 0.25), coronary artery disease (OR = 1.97, χ² = 1.91, p = 0.17 and OR = 2.63, χ² = 1.35, p = 0.25), or diabetes (OR = 1.35, χ² = 0.24, p = 0.62 and OR = 1.53, χ² = 0.24, p = 0.62).ConclusionsThe current preliminary results suggested that there was no correlation between TNF-α promoter polymorphism and diabetes, hypertension and cardiac disease among psoriatic patients in the Turkish population.

Association between TNF-α rs1800629 polymorphism and the risk of myocardial infarction: A meta-analysis.

The tumor necrosis factor-alpha (TNF-α) G-308A polymorphism has been suggested to be a susceptibility factor for myocardial infarction (MI). However, differing results from various studies have led to controversial conclusions. Hence, we performed a meta-analysis to evaluate the association between TNF-α G-308A polymorphism and MI. Reported studies published before March 30, 2015 were included and analyzed from the PubMed and Embase databases. Study selection and data extraction were carried out independently by two authors. The odds ratios (ORs) and 95% confidence intervals (CIs) were used to evaluate the association between the selected variables using the Comprehensive Meta-Analysis v2.2 software. In total, 12 publications with 13 case-control studies consisting of 6037 cases and 7262 controls were included in our meta-analysis. The overall results showed that there was no significant association between TNF-α G-308A polymorphism and MI risk [A vs G: OR = 1.18, 95%CI = 0.94-1.48; AA vs GG: OR = 1.23, 95%CI = 0.74-2.05; GA vs GG: OR = 1.22, 95%CI = 0.98-1.51; (GA+AA) vs G: OR = 1.21, 95%CI = 0.96-1.54; AA vs (GG+GA): OR = 1.16, 95%CI = 0.72-1.88]. However, when subgroup analysis was performed according to the stages of MI, results indicated that there was a significant association between TNF-α G-308A polymorphism and the risk of acute MI. Other subgroup analyses revealed no significant associations. Current evidence suggests that TNF-α G-308A polymorphism may be associated with increased risk for acute MI.

Variations in inflammatory genes as molecular markers for prediction of inflammatory bowel disease occurrence.

Research on inflammatory bowel disease (IBD) has highlighted genes involved in the regulation of inflammatory responses as contributors to disease pathogenesis. This study aimed to evaluate the associations between IBD and variations in NOD2, TLR4, TNF-α, IL-6, IL-1β and IL-1RN genes, and to use the genetic data obtained in predictive modeling. A total of 167 IBD patients and 101 healthy controls were genotyped by polymerase chain reaction-restriction fragment length polymorphism. Using the genotype data attained as the input to various classification algorithms, IBD prediction models were designed. The area under the receiver operating characteristic curve (AUROC) was used to measure their performance. Significant associations were found between Crohn's disease (CD) and minor NOD2 variants, as well as TLR4 299Gly, TNF-α G-308A, IL-6 G-174C and IL-1RN VNTR A2 variants, while ulcerative colitis (UC) was associated only with IL-1RN VNTR A2 variants. CD and UC showed highly significant difference in the allelic distribution of TNF-α G-308A, where the A allele was found to be related to CD, and the G allele to UC. A combined effect of patients' gender and TLR4 variants was observed among CD patients. When all analyzed genotype and gender data were used, prediction performance achieved a maximum AUROC of 0.690 for CD and 0.601 for UC dataset. Variations in the genes involved in immune regulation are genetic factors of importance in IBD susceptibility that could potentially be used as predictors of disease development.

Association between maternal tumor necrosis factor-α G308A polymorphism and interferon-γ A874T polymorphism and risk of preterm birth: a meta-analysis

Objective(s)This article was undertaken to investigate the association between tumor necrosis factor-α (TNF-α) G308A polymorphism and interferon-γ (INF-γ) A874T polymorphism and risk of preterm birth (PTB) by performing a meta-analysis of available studies. Study designArticles were chosen based on PubMed, EMBASE, Web of science, and China Biology Medicine (CBM) databases with no language restriction from their inceptions to 1 March, 2014. Specific inclusion criteria were used to evaluate articles. Meta-analysis was performed by using a random or fixed effect model with STATA 11.0 software. We estimated the summary odds ratios (ORs) with its corresponding 95% confidence interval (95%CI) to assess the association. Results21 eligible case–control studies with a total of 2103 cases and 5070 controls were finally included into this meta-analysis. Pooled analysis showed that A allele of TNF-α G308A was not associated with increased PTB risk (OR=0.84, 95%CI: 0.65–1.07, p=0.167 for G vs. A). Stratifying analysis for ethnicity and different definition of PTB also indicated that A allele was not associated with increased PTB risk. However, the meta-analysis showed that INF-γ A874T polymorphism was associated with the increased risk of PTB (OR=1.14, 95%CI: 1.11–1.73, p=0.004 for A vs. T). Stratifying analysis was not performed due to the small sample size. Conclusion(s)TNF-α G308A polymorphism was not associated with an increased risk of PTB, but INF-γ A874T polymorphism may contribute to increasing susceptibility to PTB. Detection of polymorphism of INF-γ A874T might be a promising biomarker for the diagnosis and prognosis of preterm delivery.

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

AimsAnemia 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. MethodsPolymorphisms in ACE, TNF-α and EPO were genotyped in 1142 patients. Anemia was defined as hemoglobin (Hb) levels below 12g/dL for women and 13g/dL for men. Results286 (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. ConclusionsThe 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.

Gene polymorphisms of tumor necrosis factor alpha and antioxidant enzymes in bronchial asthma.

Bronchial asthma is an inflammatory disease resulting from a combination of genetic and environmental factors. Single nucleotide polymorphisms in the regulatory regions of cytokine and antioxidant enzyme genes may affect cytokine production and enzyme activity, and thus play a contributory role in asthma pathogenesis. The aim of this study was to examine the association of manganese superoxide dismutase (MnSOD) Ala16Val, catalase (CAT) A-21T and tumor necrosis factor alpha (TNF-α) G-308A polymorphisms with bronchial asthma. A total of 79 patients with asthma and 95 healthy controls were screened for MnSOD Ala16Val, CAT A-21T and TNF-α G-308A polymorphisms using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The results obtained showed significantly higher prevalence of the MnSOD ValVal genotype (χ2=14.463, df=2, p=0.001) and MnSOD 16Val allele (χ2=12.862, p=0.026, OR=0.451, 95% CI=0.291-0.699) in patients with asthma compared to controls. The genotype and allele frequencies distribution of CAT A-21T and TNF-α G-308A gene polymorphisms did not show differences between patients and controls. Our results show an association of MnSOD Ala16Val genetic polymorphism with asthma in a Serbian population and suggest a protective role of the MnSOD 16Ala allele.

Association of TNF-α G308A gene polymorphism in essential hypertensive patients without type 2 diabetes mellitus.

This study aims to investigate the effects of tumor necrosis factor alpha (TNF-α) G308A gene polymorphism on essential hypertension (EHT) with or without type 2 diabetes mellitus (T2DM). The project was conducted on buccal epithelial and blood cells for case and control patients, respectively. Epithelial cells were obtained from the inner part of the cheeks. Techniques including DNA extraction, polymerase chain reaction (PCR), and restriction fragment length polymorphism (RFLP) were utilized to assess biomarkers of DNA damage. Our results demonstrated significant differences between wild and mutated genotypes among EHT patients without T2DM. We also found a significant association between wild and mutated allele frequencies in EHT patients (P < 0.05). Clinical characteristics between the groups (EHT with or without T2DM and controls) showed statistically significant association (P < 0.05). Overall, we show that G308A polymorphism of the TNF-αgene may be a significant genetic risk factor for EHT without T2DM patients in Malaysia.

TNF-αG-308A polymorphism is associated with insulin resistance: a meta-analysis.

Tumor necrosis factor-α (TNF-α) promoter polymorphisms has been reported to be associated with obesity and insulin resistance and gained widespread attention. However, results obtained so far are quite conf‍‍licting. We therefore performed a meta-analysis to address this issue, basing on 17 studies from electronic databases (MEDLINE and EMBASE). No evidence of significant effect of TNF-αG-308A polymorphism on body mass index (BMI) or obesity risk was detected (BMI: WMDRE = 0.05, 95%CI: -0.62 to 0.73; risk of obesity: ORFE = 1.09, 95%CI: 0.87 to 1.35). G-308A variant was significantly associated with increased insulin levels in the overall (SMDFE = 0.12, 95%CI: 0.03 to 0.20) and obese subgroup analysis (SMDFE = 0.16, 95%CI: 0.03 to 0.29). In total, no significant result was observed for the association between TNF-α G-308A variant and HOMA-IR index. Nevertheless, subgroup analysis showed G-308A polymorphism was significantly associated with increased HOMA-IR in Caucasians (WMDFE = 0.49, 95%CI: 0.03 to 0.94). Our results indicate that TNF-αG-308A polymorphism has a significant effect on insulin resistance. However, it is unlikely that G-308A variant contributes to obesity.

TNFα G308A polymorphism is associated with resilience to sleep deprivation-induced psychomotor vigilance performance impairment in healthy young adults.

Cytokines such as TNFα play an integral role in sleep/wake regulation and have recently been hypothesized to be involved in cognitive impairment due to sleep deprivation. We examined the effect of a guanine to adenine substitution at position 308 in the TNFα gene (TNFα G308A) on psychomotor vigilance performance impairment during total sleep deprivation. A total of 88 healthy women and men (ages 22-40) participated in one of five laboratory total sleep deprivation experiments. Performance on a psychomotor vigilance test (PVT) was measured every 2-3h. The TNFα 308A allele, which is less common than the 308G allele, was associated with greater resilience to psychomotor vigilance performance impairment during total sleep deprivation (regardless of time of day), and also provided a small performance benefit at baseline. The effect of genotype on resilience persisted when controlling for between-subjects differences in age, gender, race/ethnicity, and baseline sleep duration. The TNFα G308A polymorphism predicted less than 10% of the overall between-subjects variance in performance impairment during sleep deprivation. Nonetheless, the differential effect of the polymorphism at the peak of performance impairment was more than 50% of median performance impairment at that time, which is sizeable compared to the effects of other genotypes reported in the literature. Our findings provided evidence for a role of TNFα in the effects of sleep deprivation on psychomotor vigilance performance. Furthermore, the TNFα G308A polymorphism may have predictive potential in a biomarker panel for the assessment of resilience to psychomotor vigilance performance impairment due to sleep deprivation.