TNF-alpha Polymorphisms Research Articles

Cytokine gene polymorphisms in Japanese patients with hepatitis B virus infection—association between TGF-β1 polymorphisms and hepatocellular carcinoma

In this study, we determined the frequencies of the genotypes associated with the polymorphism of the cytokines genes, and investigated their association with the risk of hepatocellular carcinoma (HCC) in hepatitis B virus (HBV) carriers. Genetic polymorphism in the cytokines TNF-alpha, IFN-gamma, TGF-beta1, IL-6, and IL-10 were studied in 236 Japanese patients with HBV infection. The genetic polymorphisms of these cytokines were analyzed by polymerase chain reaction-sequence-specific primer (SSP). There was no statistically significant difference in the genetic polymorphisms of TNF-alpha, IFN-gamma, and IL-10 genes between HBV carriers with HCC and those without HCC. However, the TGF-beta1+29 (codon 10) C/C genotype was lower in HBV carriers with HCC than in those without HCC (HCC 14.6% vs non-HCC 31.9%). The association of HCC was significantly lower in HBV carriers with C/C genotype than in those with T/C or T/T genotype in position +29 of the TGF-beta1 gene. Our findings suggest that the genetic polymorphism in codon 10 of the TGF-beta1 gene may play a role in HCC development in patients with chronic HBV infection.

Tumour Necrosis Factor-a and Heat-Shock Protein 70-2 Gene Polymorphisms in a Family with Rheumatoid Arthritis

The aim of this work was to investigate the prevalence of TNF-alpha-308 polymorphism among the 29 members of a family with RA and the association between the MHC-linked biallelic HSP70-2 gene and the TNF-alpha polymorphism. Five of the members with RA were diagnosed by using the revised 1987 ACR criteria, and 1 member suffered from SLE. The variations in the TNF-alpha and the HSP70-2 genotypes were analyzed by PCR-RFLP, using NcoI and PstI restriction enzymes. Two of the 29 members were homozygotes for allele A, 18 were heterozygotes (TNF A/G) and 9 of them were homozygotes for allele G. Nineteen of the 29 were heterozygotes for HSP70-2 (A/G), 10 of them were homozygotes for the G allele, and none were homozygotes for allele A. Four of the 5 the RA patients carried the A allele for TNF-alpha all 5 were heterozygotes for HSP70-2 genotypes. The carriage of the A allele for TNF-alpha of -308 SNP in 4 of the 5 RA patients, and the high prevalence (68.0%) of TNF A allele carriers in this family confirms the important role of this candidate gene in the pathomechanism of RA, and might be of prognostic value for future clinical observations. Further, to test for association a much larger set of genetically independent patients and controls is needed.

Tumor necrosis factor-α-308 promoter and p53 codon 72 gene polymorphisms in women with leiomyomas

Tumor necrosis factor-alpha (TNF-alpha), a proinflammatory cytokine, plays an important role in the process of autoimmune diseases. p53 is related to the regulation of cell growth and prevention of carcinogenesis. We propose to investigate whether gene polymorphisms for TNF-alpha-308 promoter and p53 could be used as markers of susceptibility in leiomyomas. Prospective basic study. Departments of gynecology and genetics in a medical center. Group 1: leiomyoma (n = 159); group 2: non-leiomyoma (n = 131). Genomic DNA was obtained from peripheral leukocyte. The TNF-alpha and p53 gene polymorphisms were amplified by polymerase chain reaction (PCR), enzyme restriction, and electrophoresis. Two gene polymorphisms were identified: [1] the A (cuttable)/G (uncuttable) polymorphisms of the TNF-alpha gene on chromosome 6p21.3; [2] A (cuttable)/P (uncuttable) polymorphisms of the p53 gene on chromosome 17p. Genotype and allelic frequencies in both groups were compared. Genotype distribution and allele frequency of TNF-alpha gene polymorphism in both groups were significantly different. Proportions of A homozygote/heterozygote/G homozygote for TNF-alpha in both groups were: (group 1) 61%/34.6%/4.4% and (group 2) 81.7%/14.5%/3.8%. Proportions of allele A/G for TNF-alpha in both groups were: (group 1) 78.3%/21.7% and (group 2) 88.9%/11.1%. Distributions of p53 polymorphisms in both groups were not different. The proportions of A homozygotes/heterozygotes/P homozygotes for p53 were (group 1) 32.7%/42.1%/25.2% and (group 2) 28.2%/48.9%/22.9%. G homozygote and G allele for TNF-alpha promoter are related to a higher risk of leiomyomas. The p53 codon 72 gene polymorphism is not associated with the susceptibility of leiomyomas.

Increased Risk of Developing Hepatocellular Carcinoma Associated with Carriage of the TNF2 Allele of the -308 Tumor Necrosis Factor-α Promoter Gene

Tumor necrosis factor-alpha (TNF-alpha) is a cytokine that may act as an endogenous tumor promoter. A genetic polymorphism of TNF-alpha at position -308 of the promoter region, which includes TNF1 (-308G) and TNF2 (-308A) alleles, has been found to be associated with susceptibility to various types of cancer. We conducted a study to evaluate the association between this polymorphism and hepatocellular carcinoma (HCC). We recruited 74 HCC patients and 289 healthy controls, and determined their -308 TNF-alpha promoter genotypes through polymerase chain reaction followed by electrophoresis. Carriage of the TNF2 allele was associated with an increased risk of HCC (odds ratio [OR] = 3.5; 95% confidence interval [CI]:[2.1, 6.0]), and a trend toward a significant increase in the risk of developing HCC was observed from TNF1/TNF1, TNF1/TNF2, to TNF2/TNF2 genotypes (p < 0.01). After adjustment for gender, age, and markers of hepatitis B and C, the OR of developing HCC associated with TNF2 allele carriage was 5.3 (95% CI: [2.3, 12.1]; p < 0.01) Carriage of the TNF2 allele is a significant predictor of HCC independent of hepatitis B and C, and therefore it may be used as a biomarker for susceptibility to HCC.

Elevated Plasma C-reactive protein in chronically distressed subjects who carry the A allele of the TNF-alpha -308 G/A polymorphism.

Sustained psychological stress may result in a state operationalized as "vital exhaustion." Exhaustion predicted coronary artery disease (CAD) events whereby increased inflammatory activity might mediate this link. Moreover, there is an emerging importance of gene-environmental interactions in CAD. We investigated the effect of exhaustion severity on plasma levels of C-reactive protein (CRP) and whether exhaustion might regulate CRP levels via the -308G/A polymorphism of the tumor necrosis factor (TNF)-alpha gene. We assessed exhaustion in 275 industrial employees (mean age +/- SD, 41 +/- 9 years, 88% men) using the Maastricht Questionnaire. Subjects were stratified as per exhaustion severity: none (N = 80), moderate (N = 128), and severe (N = 67). The TNF-alpha polymorphism was determined by real-time polymerase chain reaction, and plasma CRP levels were measured by a high-sensitivity immunoassay. There was a significant interaction between exhaustion and the TNF-alpha polymorphism, explaining 4.5% in the variance of plasma CRP values (F(5,271) = 2.47, p =.033); the result held after controlling for classic cardiovascular risk factors. Adjusted mean CRP levels across exhaustion strata in GA (N = 70) and AA (N = 3) carriers combined were 0.91 mg/l (none), 1.78 mg/l (moderate), and 2.61 mg/l (severe) as compared with 1.24 mg/l, 1.61 mg/l, and 1.36 mg/l for the GG wild-type (N = 202). The findings suggest that the A allele of the TNF-alpha -308 G/A polymorphism may mediate inflammation with exhaustion in a dose-response relationship, while with the GG wild-type exhaustion severity seems unrelated to CRP levels. The finding provides a rationale for gene-environmental interactions by which psychosocial factors may promote atherosclerosis and CAD.

Association Between the TNF-2 Allele and a Better Survival in Cardiogenic Shock

Tumor necrosis factor (TNF)-alpha has been implicated in the pathophysiology of heart failure. We explored a possible association between TNF-alpha, interleukin (IL)-6, IL-10, transforming growth factor (TGF)-beta, and interferon (IFN)-gamma cytokine polymorphisms, their in vivo production, and mortality from cardiogenic shock. Prospective, observational study. Thirty-one bed, university, medicosurgical department of intensive care. Thirty-three adult patients with cardiogenic shock of recent (< 4 h) onset. None. TNF-alpha, IL-6, IL-10, TGF-beta1, and IFN-gamma plasma levels were measured by enzyme-linked immunosorbent assay. Polymorphisms of TNF-alpha within the promoter at position -308a-->g, IL-6 within the promoter at position -174c-->g, IL-10 within the promoter at position -1082a-->g/-819t-->c and -819t-->c/-592a-->c, TGF-beta1 at codon 10t-->c and codon 25c-->g, and IFN-gamma at intron 1 at position + 874t-->a were studied. The 33 patients had a mean (+/- SD) age of 64 +/- 17 years and a mean simplified acute physiology score II of 62.3 +/- 15.3. Twenty-three patients (70%) died in the ICU, including 21 of 26 patients (81%) in the TNF-1 group but only 2 of 7 patients (29%) in the TNF-2 group (p = 0.016). There were no significant differences in median plasma TNF-alpha levels between the TNF-1 and the TNF-2 groups, but TGF-beta1 levels were higher in the survivors than in the nonsurvivors (median, 866 pg/mL; range, 384 to 1,966 pg/mL; vs median, 454 pg/mL; range, 167 to 1,266 pg/mL, respectively; p = 0.02). There were no significant differences in TNF-2 polymorphism between the patients with cardiogenic shock and a group of healthy control subjects (7 of 33 patients vs 13 of 48 subjects, respectively; p = 0.61), but IFN-gamma polymorphism was less common in the cardiogenic shock group (p = 0.034). Patients with the TNF-2 allele have no greater risk of cardiogenic shock but a better survival rate when it develops. Different genetic factors appear to influence the risk of development of, and outcome from, cardiogenic shock.

P0386 GENETIC POLYMORPHISMS AND COELIAC DISEASE

Introduction: Coeliac disease is dependent on genetic susceptibility. Various candidate genes have been suggested, as is shown by genome linkage and case control studies. Cytoquine coding genes may be relevant due to the inflammatory pattern of the disease. There is no homogeneity in different populations concerning the TNF-alpha polymorphisms and no studies have evaluated the importance of IL-1 related genes in genetic susceptibility. Methods: TNF-alpha promoter allele TNF 308*A, IL-1 eta511*T and ILRN VNTR were screened in 39 patients with celiac disease (median age 13.6 years, range 2–20 years), from the North of Portugal. Total DNA was extracted from blood samples and SSCP analysis was made and sequencing was performed. Diagnosis was based in clinical details, antibody titers and histological confirmation. All patients were under strict gluten-free diet. Results: The analyzed population had a male/female ratio of 0.4/1. The allele TNF 308*A was found in 51.3% of patients (OR=3.3, IC 1.7–6.6). The allele IL-1 eta 511*T was found in 64.8% (OR=1.5, IC 0.7–3.0) and in 16.7 % for the genotype ILRN VNTR 2*/2* (OR=1.9, IC 0.7–5.0). Conclusion: In addition to HLA there are inflammatory genes that may be relevant in genetic susceptibility to celiac disease. The promoter allele TNF 308*A showed strong association with the disease. There was no association between alleles IL-1 eta 511*T and ILRN VNTR 2*/2*. Further studies with larger series may confirm these data.

Susceptibilidad genética y riesgo de cáncer gástrico en una población del Cauca.

Gastric cancer (GC) is the main cause of mortality by cancer in Colombia. Glutathione S-transferase (GST) enzymes are involved in the detoxification of many environmental carcinogens. The homozygous deletions of glutathione S-transferase M1 (GSTM1-0) and glutathione S-transferase T1 (GSTT1-0) have been associated with several types of cancer. The risk to develop GC has been associated with environmental factors and Helicobacter pylori infection. The tumor necrosis factor (TNF-alpha) and its levels are increased in patients infected with H. pylori. A G/ A transition in the position -308 of the promoter of the TNF-alpha has been related in several studies to an increased expression of the gene and is associated with susceptibility to GC. The association of these polymorphisms with GC and the interaction with other risk factors (life style) were investigated. Blood samples were obtained from 46 GC patients and 96 controls. The logistic regression model was used to obtain the odds ratio (OR) and their 95% confidence intervals. These statistics established the association between the enzymatic polymorphisms and GC and between other independent factors and GC. The frequency of the TNF-alpha polymorphism in people infected with H. pylori was 18% in the GC population and 7% in the control group. This transition was not significantly associated with H. pylori infection and GC. The frequencies of the deletion polymorphisms for patients and controls were as follows: GSTM1 65.2% and 37.5%; GSTT1 17.4% and 14.6%. These results suggested that the GSTM1 deletion polymorphism was associated with an increased risk of gastric cancer (OR of 5.5; 95%CI, 1.7-17.2). Furthermore, other risk factors such as H. pylori infection (OR 5.58, CI 1.8-17.2), smoking (OR 6.70, CI 2.2-20.3) and alcohol intake (OR 3.27, CI 1.1-9.4) were associated with GC.

Polymorphism of stress protein HSP70-2 gene in Tunisians: susceptibility implications in type 2 diabetes and obesity

Tumor necrosis factor alpha (TNFalpha) is expressed primarily in adipocytes and elevated levels of this cytokine have been linked to obesity and insulin resistance. Several studies have shown statistical evidence of linkage between obesity and the chromosomal region encompassing the TNFalpha gene, suggesting that TNF alpha and/or a nearby gene is involved in the pathogenesis of obesity. Recently we analyzed the -308 TNFalpha polymorphism and that of HSP70-2 gene in Tunisian patients with obesity and no significant difference in allele frequencies of the -308 TNFalpha polymorphism was found between obese patients and controls. In contrast, polymorphism in HSP70-2 gene was found to be highly associated with obesity. Both TNFalpha and HSP70-2 genes have been mapped within the major histocompatibility complex (MHC). We designated a case-controlled study to investigate a potential association of genetic variation of the TNFalpha and that of the heat shock protein 70-2 (HSP70-2) with type 2 diabetes. We used the polymerase chain reaction and restriction enzyme to characterize the variation of the TNFalpha promoter region and that of the HSP70-2 gene in 280 unrelated Tunisian patients with type2 diabetes and 274 healthy control subjects. Analysis of the -308 TNFalpha polymorphism in patients with type 2 diabetes and in control subjects revealed that the heterozygous TNF1/TNF2 genotype was significantly less frequent in the patient group (p=0.003), suggesting that TNF1/TNF2 may be considered as a protective marker against type 2 diabetes (OR=0.58). In contrast, a significant relative risk of type 2 diabetes was found associated with the P2-HSP70-2 homozygous genotype in non obese diabetic subjects (OR=1.97; p=0.0012). These results along with those showing high frequency of P2-HSP70-2 genotype in obese Tunisians, suggest that HSP70-2 polymorphism has susceptibility implications in both obesity and diabetes.

Association of IL-1beta, IL-1ra, and TNF-alpha gene polymorphisms in childhood nephrotic syndrome.

We investigated the association between IL-1beta, IL-1ra, and TNF-alpha gene polymorphisms and childhood nephrotic syndrome (NS). We analyzed the genetic polymorphism of IL-1beta, IL-1ra, and TNF-alpha genes in 152 patients with childhood NS and 292 healthy adult controls. The C to T exchange at position -511 of IL-1beta and the G to A at -308 of the TNF-alpha gene were genotyped. Five alleles of the IL-1ra gene were identified and designated as IL1RN*1, IL1RN*2, IL1RN*3, IL1RN*4, and IL1RN*5, according to the variable number of tandem repeats in intron 2. The allele frequencies of IL-1beta1 (-511C), IL-1beta2 (-511T), TNF1 (-308G), and TNF2 (-308A) were 53.0, 47.0, 92.1, and 7.9%, respectively, in the childhood NS group. This was not significantly different from normal controls. In the childhood NS group, the allele frequencies of IL1RN*1, IL1RN*2, IL1RN*3, IL1RN*4, and IL1RN*5 were 90.8, 7.6, 1.6, 0, and 0% [IL1RN*1 odds ratio (OR)=0.296, P=0.0001, IL1RN*2 OR=3.902, P=0.0002]. A high allele frequency of IL1RN*2 and a lower allele frequency of IL1RN*1 were found in childhood NS, although there was no association with IL-1beta and TNF-alpha. A high allele frequency of the IL1RN*2 allele may affect disease susceptibility in childhood NS.

Association between tumor necrosis factor-alpha promoter polymorphism and Alzheimer's disease.

Tumor necrosis factor-alpha (TNFalpha) gene polymorphisms have been reported to be associated with Alzheimer's disease (AD) in Caucasian populations. Three TNFalpha polymorphisms (-857, -863, and -1,031) were studied in a Chinese population. A high-risk TNFalpha haplotype (-1,031C-863C-857C) with an odds ratio of 2.54 (95% CI 1.37 to 4.79) for AD was identified. No interaction effect of APOE and TNFalpha genotypes was found, but both acted as important risk factors for AD.

Cytokine gene promoter polymorphisms and mortality in acute renal failure.

Although cytokines play a pivotal role in the inflammatory responses that mediate the severity of acute renal failure (ARF), the importance of pro- and anti-inflammatory cytokine gene promoter polymorphisms has been unexplored. We prospectively evaluated the relationship of single nucleotide polymorphism in the promoter region of tumor necrosis factor alpha (TNF-alpha) and interleukin-10 (IL-10) to mortality in 61 patients with ARF requiring intermittent hemodialysis. Cytokine genotyping was performed on leukocytes using PCR techniques. Cox proportional-hazards regression analysis was used to explore these relationships. The mean (+/-SD) APACHE II score was 24 +/- 7, MOF score 2 +/- 1, and 64% had sepsis. The TNF-alpha high producer genotype (-308 A-allele carrier) was associated with a higher risk of death after adjustment for the APACHE II score (HR=2.5; P=0.04), and the IL-10 intermediate/high producer genotype (-1082 G-allele carrier) was associated with a lower risk of death after adjustment for the MOF score (HR=0.36; P=0.03). Considering combinations of genotypes, the TNF-alpha high and IL-10 low producer genotype combination was associated with a approximately 6-fold increased risk of death compared to the TNF-alpha-low and IL-10 intermediate/high producer genotype combination, after adjustment for either APACHE II (P=0.004), MOF score (P=0.004) or sepsis (P=0.006). TNF-alpha and IL-10 gene polymorphisms are related to the risk of death among patients with ARF who require dialysis. Larger studies are needed to confirm these relationships.

A NOTCH4 association with multiple sclerosis is secondary to HLA-DR*1501.

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) with supposedly autoimmune features known to be associated with a specific HLA DR-DQ haplotype (DR15, DQ6, or HLDRB1*1501,DRB5*0101,DQA1*0102,DQB1*0602). We have previously reported that the associated haplotype extends to HLA-B and described an independent association with HLA-A alleles in MS. Owing to a complex situation with extensive linkage disequilibria, it is still unclear whether classical HLA genes are responsible or whether associations may be due to other genes in this region. Here, we analyzed an association in MS with the NOTCH4 and TNFalpha (tumor necrosis factor-alpha) genes, located between the HLA-DRB1 gene and the HLA-A gene. For NOTCH4, located 0.4 Mb telomeric to HLA-DRB1, an SNP at position -25 and a trinucleotide repeat were investigated in 181 MS patients, and 180 controls also typed P = 0.027 for HLA-DRB and HLA-A. A modest association was observed (OR = 3.44) with the C-25 allele. However, two-locus analysis revealed that this association was secondary to the classical association with HLA-DRB1. For TNF, located 0.7 Mb telomeric of NOTCH4, SNPs at positions -308 and -238 were studied in the same dataset. We found no association between these TNFalpha gene polymorphisms and MS in this dataset, although there was linkage disequilibrium (LD) between DRB1 and TNF and between HLA-A and TNF. We conclude that alleles of the NOTCH4 and TNFalpha genes are unlikely to be of importance for the susceptibility to MS, although specific alleles of these genes are often carried on the same haplotype as DR15, DQ6.

Basal cell carcinoma is associated with high TNF-alpha release but nor with TNF-alpha polymorphism at position--308.

The mechanisms underlying induction of UVB-induced immunosuppression are not fully understood, but tumor necrosis factor alpha (TNF-alpha) is suggested to play a central role. A single base pair polymorphism at position --308 in the promoter region of the TNF-alpha gene associated with an enhanced secretion of TNF-alpha has been identified in humans. We have therefore investigated the association of the --308 polymorphism with the risk of basal cell carcinoma (BCC) in humans. The frequency of TNF G and TNF A alleles among Caucasian patients with a previous BCC (n=191) and health adults (n-107) were compared. For the TNF--308 polymorphism there was significant association between the genotype or allele frequencies and having BCC. To determine whether patients with a previous BCC had an increased capacity to secrete TNF-alpha, mononuclear cells were stimulated with lipopolysaccharide. Mononuclear cells from patients with a previous BCC (n=15) demonstrated a significantly increased release of TNF-alpha upon stimulation with lipopolysaccharide (P<0.03) compared with mononuclear cells age-matched control subjects (n=16). Further studies of other polymorphisms of the TNF-alpha gene associated with increased TNF-alpha production and BCC and necessary.

Helicobacter pylori and gastric diseases.

Helicobacter pylori (H. pylori) infection is a pathogenic agent of gastric diseases, but their mechanisms are unclear. Effects of ammonia, tumor necrosis factor (TNF), and anti-Lewis autoantibodies induced after H. pylori infection on the development of gastric diseases were investigated. Ammonia disturbed the collagen metabolism in the ulcer base. Soluble TNF receptors regulate the action of TNF. The involvement of anti-Lewis autoantibodies in the development of peptic ulcer might be unlikely. Moreover, H. pylori-specific IgA in gastric juice and TNFalpha gene polymorphism in persons infected with H. pylori were studied. According to H. pylori-specific IgA titer in gastric juice, persons were divided into two histologically and endoscopically different states of disease. TNFA -857 single nucleotide polymorphism (SNP) may be associated with rugal hyperplastic gastritis and gastric carcinomas without severe atrophy. However, complete elucidation of pathogenic mechanisms of H. pylori-induced gastric diseases requires further research.

Polymorphisms in tumour necrosis factor-alpha, transforming growth factor-beta, interleukin-10, interleukin-6, interferon-gamma, and outcome of hepatitis C virus infection.

Cytokines play a key role in the regulation of immune responses. In hepatitis C virus infection (HCV), the production of inappropriate cytokine levels appears to contribute to viral persistence and to affect response to therapy. Cytokine genes are polymorphic at specific sites, and certain mutations located within coding/regulatory regions have been shown to affect the overall expression and secretion of cytokines. The aim of this study was to investigate the frequency of genotypes associated with polymorphisms of TNF-alpha, TGF-beta, IL-10, IL-6, and IFN-gamma and to determine their association with the outcome of HCV infection. Genotyping was carried out by polymerase chain reaction sequence-specific primers on genomic DNA isolated from 158 individuals. Of these, 66 had spontaneously recovered from infection (persistently HCV RNA negative), while 92 had persistent infection (persistently HCV RNA positive). All patients were genotyped as high or low producers of TNF-alpha and IL-6 and high, intermediate, or low producers of TGF-beta, IL-10, and IFN-gamma based on single nucleotide substitutions. A significant proportion of patients with viral clearance were genotyped with a low IL-6 production profile, whereas those with persistent infection were genotyped with a high production profile (P = 0.02). No associations were observed between polymorphisms of TNF-alpha, IL-10, or IFN-gamma and viral clearance or persistent infection. Furthermore, there were no associations between cytokine genotypes and severity of disease. Inheritance of some genotypes associated with polymorphisms of cytokine genes, such as IL-6, may be host genetic factors associated with outcome of HCV in a well-defined ethnically homogeneous cohort.

The HLA class III subregion is responsible for an increased breast cancer risk.

BRCA1 and BRCA2 germline mutations account for <5% of breast cancer cases. Less penetrant breast cancer susceptibility genes are likely to exist. Earlier studies have suggested involvement of the HLA region. The HLA region was genotyped with 24 microsatellite markers and markers for two single nucleotide polymorphisms (SNPs) in TNFalpha and TNFbeta, in germline DNA from 956 breast cancer patients and 1271 family-based controls. Association analyses and the haplotype sharing statistic (HSS) were used to search for differences in haplotype sharing between patients and controls. Based on criteria known to influence genetic breast cancer risk, patients were divided into groups of high, moderate and low risk. The HSS revealed a significant difference in mean haplotype sharing between patients and controls for four consecutive markers (D6S2671, TNFa, D6S2672 and MICA), the highest being at D6S2671 (P=0.017). Subgroup analyses showed that moderate-risk patients were responsible for this difference, with the strongest association for D6S2672 (P=0.0009). A single haplotype was more frequent and longer in moderate-risk patients than in controls. The results were confirmed with association analyses. Individuals homozygous for haplotype 110-184 (D6S2672-MICA) were observed in 9.0% of moderate-risk patients and 1.5% of controls [odds ratio (OR)=7.14], while heterozygotes were at a lower risk (OR=1.41), suggesting a recessive effect. No association was observed between the two SNPs in TNFalpha (-308) and TNFbeta (intron 1) and breast cancer risk. The results reveal a potential role of the HLA class III subregion in susceptibility to breast cancer in patients at moderate familial risk.

Relationship between the tumor necrosis factor alpha polymorphism and the serum C-reactive protein levels in inflammatory bowel disease.

Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gastrointestinal tract, including ulcerative colitis (UC) and Crohn's disease (CD). The aim of the study was to determine the prevalence of the tumor necrosis factor alpha (TNF-alpha) promoter polymorphisms at positions -238 and -308, and to measure the serum CRP levels in CD and UC patients and in a healthy population. The TNF-alpha gene polymorphisms were determined by the PCR-RFLP method. Samples of 74 CD and 50 UC patients and 138 healthy Hungarian volunteers were examined. The G-->A substitution at position -308 (designated the TNF2 allele) was significantly less frequent among IBD patients than in the control group (P=0.0009); 15% of the CD patients and 18% of the UC patients carried the mentioned allele, which was significantly less frequent compared with the healthy population (33%, P=0.0035 and P=0.036, respectively). No difference in the G-->A substitution at position -238 was observed. We found the median CRP levels to be significantly higher in the active phase of the disease than in the inactive phase among the -308A allele carriers (P=0.002), while this difference was not significant when the CRP levels in the active and inactive phases were compared among the -308GG homozygous patients (P=0.084). The decreased frequency of the TNF2 allele (known to be associated with elevated TNF-alpha production) in IBD may determine the severity of IBD through its interaction with plasma CRP levels, and may modify the pathogenesis of this chronic inflammatory disease.

Tumor necrosis factor-alpha promoter polymorphisms in Mexican patients with rheumatic heart disease

The major histocompatibility genes (MHC) have been associated with the genetic susceptibility to rheumatic heart disease (RHD). Results have been inconsistent and new genes located on the MHC region such as tumor necrosis factor (TNF-alpha) need to be analyzed. TNF-alpha polymorphisms (positions -238 and -308) were determined in 87 RHD Mexican Mestizo patients and 101 healthy controls. Patients were classified into mitral valve damage (MVD) and multivalvular lesion (MVL) categories. TNF-238 G allele and GG genotype were increased in patients when compared to healthy controls (pC=0.001, OR=14.1 and pC=0.003, OR=14.1, respectively). Also, decreased frequencies of TNF-238 A allele (pC=0.001) and AG genotype (pC=0.003) were found. TNF-308 polymorphism analysis showed increased frequencies of T2 (A) allele (pC<10 −3, OR=10.8) and T1T2 (AG) genotype (pC<10 −3, OR=9.85) and decreased frequencies of T1 (G) allele and T1T1 (GG) genotype (pC<10 −3). When comparing valvular damage to healthy controls, patients with MVD showed increased frequencies of -238 GG (pC=0.03, OR=ND), -308 T1T2 (AG) (pC<10 −3, OR=14) and -308 T2 (A) (pC<10 −3, OR=11.7). Also, this group showed decreased frequencies of T1 (G) allele and T1T1 (GG) genotype (pC<10 −3). Patients with MVL presented increased frequency of -308 T2 (A) allele (pC=0.0003, OR=8.65) and decreased frequencies of -308 T1 (G) allele and -308 T1T1 (GG) genotype (pC=0.0003 and pC=0.006, respectively). Distribution of -238 and -308 polymorphisms were similar between MVD and MVL. The data demonstrate that RHD is associated with TNF-alpha polymorphisms in the Mexican population; however, these polymorphisms do not have relation with the valve damage.

Tumour necrosis factor-alpha polymorphism as one of the complex inherited factors in pemphigus.

The aim of our study was to analyse a significance of tumour necrosis factor (TNF)-alpha promoter gene polymorphisms in relation to the HLA-DR locus in genetic predisposition to pemphigus. TNF-alpha gene polymorphisms in position -238 and -308 were identified using a modified polymerase chain reaction-restriction fragment length polymorphism method in 53 patients with pemphigus (38 with pemphigus vulgaris, 15 with pemphigus foliaceus) and 87 healthy controls. The HLA-DRB1 locus was typed using the polymerase chain reaction SSO method in all the patients and 152 population controls. Carriers of the TNF-alpha polymorphic -308 A allele were found to be more frequent in the pemphigus foliaceus group in comparison with the control group (odds ratio (OR) = 8.12; p = 0.0005). A significant association between HLA-DRB1*04 (OR = 3.86; pcor = 0.0001) and DRB1*14 (OR = 8.4; pcor = 0.0001) and pemphigus vulgaris was found. In this group of patients a decreased frequency of HLA-DRB1*07 (OR = 0.08; pcor = 0.006) was also identified. We have shown for the first time a positive association of TNF-alpha polymorphism in position -308 with pemphigus foliaceus.