Tumor necrosis factor-alpha-308 gene polymorphism in Croatian and Slovenian multiple sclerosis patients

Lack of association between TNFA and TNFB polymorphisms and the risk of multiple sclerosis: a meta-analysis from 37 studies

BACKGROUND

Epidemiological studies about the association between genetic polymorphisms in TNFA, TNFB, and IFNG and the risk for multiple sclerosis (MS) have been performed extensively. However, the results are inconclusive. The purpose of this meta-analysis was to evaluate the contribution of the polymorphisms in TNFA, TNFB, and IFNG to the susceptibility of MS.

METHODS

The PubMed, Web of Science, and China National Knowledge Infrastructure databases were searched to identify relevant studies up to October 2021. A meta-analysis was performed and pooled odds ratios (OR) and confidence intervals (CI) were computed using fixed or random effects models.

RESULTS

A marginally significant association of the IFNG +874AT genotype with high risk of MS was observed in a heterozygous comparison (OR = 1.51, 95% CI, 1.02-2.23). However, no significant association between the TNFA (-308G/A, -238G/A, and -376G/A) and TNFB +252A/G polymorphisms and MS risk was observed both in overall analysis and in subgroup analysis.

CONCLUSION

This meta-analysis provides evidence that the TNFA (-308G/A, -238G/A, and -376G/A) and TNFB +252A/G polymorphisms were not risk factors for the occurrence of MS. Further studies with larger samples are necessary to reach the concise results about the contribution of other polymorphisms to the risk of MS.

Association of polymorphism -308G/A in tumor necrosis factor-alpha gene (TNF-α) and TNF-α serum levels in patients with relapsing-remitting multiple sclerosis

TNF-α is an important cytokine of the inflammatory response involved in the pathogenesis of relapsing-remitting multiple sclerosis (RRMS). The aim of this study is to explore the association between the promoter polymorphism -308G/A in the TNF-α gene (rs1800629) with genetic susceptibility to RRMS.Methods: A group of 183 RRMS patients and 169 age and gender-matched healthy controls were enrolled in the study. Genotyping of the polymorphism was performed by PCR-restriction fragment length polymorphism and quantification of TNF-α serum levels was conducted by ELISA.Results: The genotype distribution in female patients showed a significantly elevated frequency of heterozygotes (AG) (23.5% vs. 12.8%, OR = 2.072, p = 0.029) in comparison with the healthy women. Substantially higher TNF-α serum levels were observed in females compared to males, in both patients and healthy controls (p < 0.05). According to the genotype, TNF-α levels in the RRMS group were calculated in the following order: for GA/AA genotypes (5.67pg/ml vs. 3.48pg/ml, p = 0.0031) and for GG genotypes (4.58pg/ml vs. 3.52pg/ml, p = 0.00043). Moreover, the carriers of at least one A-allele of -308G/A TNF-α polymorphism (GA+AA) are significantly associated with two fold increased risk for RRMS development (OR = 1.950; p = 0.042) in women in contrast to men as well as associated with early onset of the disease (OR = 2.400; p = 0.021).Conclusion: Our study showed that the level of TNF-α in the serum of patients with RRMS showed a significant association with the -308G/A TNF-α polymorphism and gender dependency.

Tumour necrosis factor alpha (TNF-α) genetic polymorphisms and the risk of autoimmune liver disease: a meta-analysis

Epidemiological studies have evaluated the association between tumour necrosis factor alpha (TNF-α)- 308G/A and (TNF-α)- 238G/A polymorphisms, and the risk of autoimmune liver disease (AILD), yet the results are conflicting. To derive a more precise estimation of the relationship, we performed this meta-analysis. A systematic review was conducted to identify all eligible studies of TNF-α polymorphisms and AILD risk. We used odds ratios (ORs) with 95% confidence intervals (CIs) to assess the strength of the association between the two TNF-α polymorphisms and AILD risk. A total of 15 eligible studies were identified. Overall, positive associations of -308G/A polymorphism with AILD risk were found (A vs G allele: OR =1.45, 95%CI = 1.13- 1.86; AA vs GG: OR = 2.74, 95%CI = 1.51- 4.96; GA vs GG: OR = 1.46, 95%CI = 1.11- 1.92;dominant model: OR = 1.57, 95%CI = 1.18- 2.10; recessive model: OR = 2.22, 95%CI = 1.31- 3.76). In subgroup analysis by ethnicity, a significantly higher risk was found in Caucasians. In subgroup analysis by AILD category, significant association was observed in autoimmune hepatitis and primary sclerosing cholangitis, especially in Caucasians. Patients carrying TNF-α-238A allele had a slightly decreased risk of developing AILD (OR = 0.65, 95%CI = 0.48- 0.87). However, we found both TNF-α polymorphisms were not associated with primary biliary cirrhosis risk, even in subgroup analysis. Our meta-analysis suggests that the TNF-α-308G/A and -238G/A polymorphisms may contribute to AILD susceptibility in Caucasians,especially for autoimmune hepatitis and primary sclerosing cholangitis. Nevertheless, we found both TNF-α polymorphisms were unlikely to be associated with the risk of primary biliary cirrhosis

Single nucleotide polymorphisms in multiple sclerosis: disease susceptibility and treatment response biomarkers

Multiple sclerosis (MS) is a chronic inflammatory demyelinating and neurodegenerative disease of the central nervous system characterized by unpredictable and variable clinical course. Etiology of MS involves both genetic and environmental factors. New technologies identified genetic polymorphisms associated with MS susceptibility among which immunologically relevant genes are significantly overrepresented. Although individual genes contribute only a small part to MS susceptibility, they might be used as biomarkers, thus helping to identify accurate diagnosis, predict clinical disease course and response to therapy. This review focuses on recent progress in research on MS genetics with special emphasis on the possibility to use single nucleotide polymorphism of candidate genes as biomarkers of susceptibility to disease and response to therapy.

Tumor necrosis factor alpha 308 G/A polymorphism and Guillain-Barré syndrome risk

Guillain-Barré syndrome (GBS) is an inflammatory disorder that may implicate proinflammatory cytokines such as tumor necrosis factor alpha (TNF-alpha) in its pathogenesis. The association between TNF-alpha 308 G/A polymorphism and GBS largely remains unknown. The aim of this study was to investigate the association between TNF-alpha 308 G/A polymorphism and GBS in Chinese Han patients. TNF-alpha 308 G/A polymorphism in 150 GBS patients and 150 healthy controls were studied using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. Patients with GBS had a significantly higher frequency of TNF-alpha 308AA genotype [odds ratio (OR) = 3.79, 95% confidence interval (CI) = 1.03, 13.94; P = 0.04] than controls. When stratified by the GBS subtype, there was a significantly higher frequency of TNF-alpha 308AA genotype in patients with AMAN (OR = 6.05, 95% CI = 1.45, 25.31; P = 0.01) and AMSAN (OR = 5.56, 95% CI = 1.18, 26.23; P = 0.03) than controls. There was no significant difference in the distribution of each genotype between patients with AIDP and the control group. These data indicated that TNF-alpha 308AA genotype was associated with a higher risk of GBS in Chinese population, especially to AMAN and AMSAN.

-308 G > A of TNF-α gene promoter decreases the risk of multiple sclerosis: a meta-analysis

BACKGROUND

Environmental and genetic factors are thought to be involved in the pathogenesis of multiple sclerosis (MS). Polymorphisms of tumor necrosis factor (TNF)-α -308 were implicated in MS risk in several case-control association studies. However, the studies have shown inconsistent results.

OBJECTIVES

To address the association of G/A polymorphisms of TNF-α -308 with MS risk by meta-analysis.

METHODS

Thirteen studies were included. Pooled odds ratios (ORs) together with 95% confidence intervals (CIs) were calculated.

RESULTS

A total of 1870 cases and 2769 controls were included in the meta-analysis. The pooled result indicated that -308 A allele is significantly associated with reduced risk of MS compared with -308 G allele (A vs. G, p=0.022). The same pattern of the result was also obtained in the contrasts of AA+ GA vs. GG (p=0.008) and GA vs. GG (p=0.007). For AA vs. GG or AA vs. GA + GG, no significant association was detected most likely caused by very low frequency or non-availability of homozygote genotype AA for all of the studies.

CONCLUSIONS

TNF-α -308 A allele is associated with reduced risk of MS.

Tumour necrosis factor alpha gene (TNF-alpha) -376 polymorphism in Hungarian patients with primary progressive multiple sclerosis

Tumour necrosis factor alpha (TNF-alpha) is associated with clinical activity in relapsing-remitting multiple sclerosis (RRMS) and the development of progressive disease. Our aim was to investigate the TNF-alpha -376 polymorphism in primary progressive MS (PPMS) patients. Polymerase chain reaction and restriction fragment length polymorphism were carried out on 45 PPMS patients, 45 age and sex-matched RRMS patients and 45 healthy controls (HC). The GG genotype and the guanine allele (G) were detected significantly more often in the PPMS group as compared with the HC group (p=0.027; p=0.032). The G allele may be one of the factors responsible for progression in PPMS.

Selected markers of cardiovascular disease in a population exposed to arsenic from drinking water

This study examined prevalence and serum levels of selected markers of cardiovascular disease in 34 subjects from a Croatian rural population exposed to high levels of arsenic (As) from drinking water (611.89±10.06μg/l). The prevalences of overweight and obese subjects in the population were 32% and 35%. Half the subjects had hypertension, 29% had increased fasting serum glucose level and two were diabetic. Median total cholesterol (5.82mmol/l) and triglycerides (2.15mmol/l) were above the desirable margins. The median C-reactive protein level (1.20mg/l) was slightly higher than previously reported for healthy subjects. Serum Hsp70 level was significantly higher in nonsmokers. Total urinary As levels were positively correlated with age-adjusted serum levels of cobalamin. Near significance were also serum total bilirubin, antibodies to Hsp60 and folate. Tentative investigation of risk factors among subjects classified by tumor necrosis factor-α -308G/A and interleukin-6-174G/C gene polymorphisms was also performed. Collectively, the results are in agreement with the hypothesis of As-induced and/or compounded cardiovascular disease.

The genetics of clinical outcome in multiple sclerosis

Multiple sclerosis (MS) is a common inflammatory disease of the central nervous system (CNS), the clinical course of which varies considerably between patients. Genetic complexity and interactions with as yet unknown environmental factors have hindered researchers from fully elucidating the aetiology of the disease. In addition to influencing disease susceptibility, epidemiological evidence suggests that genetic factors may affect phenotypic expression of the disease. Genes that affect clinical outcome may be more effective therapeutic targets than those which determine susceptibility. We present in this review a comprehensive survey of the genes (both MHC- and non-MHC-related) that have been investigated for their role in disease outcome in MS. Recent studies implicating the role of the genotype and epistatic interactions in the MHC in determining outcome are highlighted.

Recent advances in genetic analysis of multiple sclerosis: genetic associations and therapeutic implications

Epidemiological studies have confirmed that genetic factors are a key component in the pathogenesis of multiple sclerosis (MS) and that those determining MS susceptibility have been extensively studied. Many papers have been published regarding the heritable differences useful in genetic studies; these include variations in DNA, such as single-nucleotide polymorphisms, microsatellites and insertion/deletion polymorphisms. However, to date, among other regions, HLA is the only region confirmed to possess genes that determine MS susceptibility. In this article, we review the progress during the last 5 years in the studies on the susceptibility genes and the pharmacogenetics of MS. Newer techniques and methods of analysis will hopefully result in better screening of individuals who are at highest risk and novel treatments.