TNF-alpha promoter polymorphisms and extended HLA and TNF-alpha haplotypes in Koreans based on 100 families

Cytokine gene polymorphisms and Parkinson's disease: a meta-analysis

BACKGROUND

Cytokines, which are involved in immunological responses, play and important role in the development and progression of Parkinson's disease (PD). The functional polymorphisms identified in cytokine genes are thought to influence PD risk. However the findings of studies investigating the association between cytokine gene polymorphisms and PD risk are still controversial. Therefore, we conducted a meta-analysis, in order to investigate the potential associations between cytokine gene polymorphisms and PD.

METHODS

Studies of PD and cytokine polymorphisms were identified by searches of PubMed and PDGene. Pooled analyses were performed to assess the association between cytokine gene polymorphisms and PD.

RESULTS

Our results indicated a positive association of TNFα -1031 CC genotype in overall analysis(CC vs. TT: OR=3.146; 95%CI: 1.631-6.070, p=0.008; CC vs. CT+TT: OR=3.187: 95%CI: 1.657-6.128,p=0.008), and an Asian subgroup, C variant(OR=1.328; 95%CI: 1.053-1.675, p=0.034) also conveyed an increased PD risk as well as CC genotype ( CC vs. TT: OR=3.207; 95%CI: 1.614-6.373, p=0.004; CC vs. CT+TT: OR=3.238; 95%CI: 1.636-6.410, p=0.004). A decreased risk for PD was associated with IL-6-174C allele (OR=0.761; 95%CI: 0.641-0.903, p=0.008) and IL-1RA VNTR 2 allele(OR=0.641; 95%CI: 0.456-0.826 p=0.004). For the polymorphisms of IL-1β C[-511]T, IL-1α C[-889]T , TNFα G[-308]A, and IL-10 G[-1082]A no significant association was found between the gene polymorphisms and PD risk.

CONCLUSIONS

Our meta-analysis suggested that gene polymorphisms of TNFα -1031, IL-6-174 and IL-1RA VNTR may be associated with PD risk. However, more large well-designed studies will be necessary to validate our findings.

Association of HLA-DR and -DQ Genes with Familial Moyamoya Disease in Koreans

OBJECTIVE

Moyamoya disease (MMD) is an uncommon cerebrovascular disorder, characterized by progressive occlusion at the terminal portion of the internal carotid artery. Incidence of the disease is high in East Asia and familial MMD accounts for about 15% of the disease. Although the pathogenesis is unknown, association of HLA class I or II alleles with MMD has been reported with conflicting results. We investigated whether there is a difference in HLA class II association between familial and non-familial forms of the disease.

METHODS

A total of 70 Korean children with MMD, including 16 familial cases (10 probands), and 207 healthy controls were studied. Among familial cases, only 10 probands were used for the HLA frequency analysis. High resolution HLA-DRB1 and DQB1 genotyping was performed using polymerase chain reaction (PCR)-sequence specific oligonucleotide hybridization and PCR-single strand conformation polymorphism methods.

RESULTS

The phenotype frequencies of HLA-DRB1(*)1302 (70.0%) and DQB1(*)0609 (40.0%) were significantly increased in familial MMD compared to both controls [vs. 15.5%, corrected p (p(c)) = 0.008, odds ratio (OR) = 12.76; vs. 4.3%, p(c) = 0.02, OR = 14.67] and non-familial MMD patients (vs. 14.8%, p(c) = 0.02, OR = 13.42; vs. 1.9%, p(c) = 0.02, OR = 35.33). The frequencies of DRB1 and DQB1 alleles in non-familial MMD patients were not significantly different from those in controls.

CONCLUSION

Our findings suggest that the genetic polymorphism of HLA class II genes or other closely linked disease relevant gene(s) could be a genetic predisposing factor for familial MMD.

Cytokine promoter polymorphisms in Taiwanese patients with Graves' disease

OBJECTIVES

This study aimed to examine the association between promoter polymorphisms of Th1 and Th2 cytokine genes [interleukin-4 (IL-4 T-34C, A-81G, C-285T and T-589C), IL-6 (G-174C), IL-10 (A-592C and T-819C) and tumour necrosis factor-alpha (TNF-alpha G-238A and G-308A)] and Graves' disease (GD) in Taiwanese population.

DESIGN AND METHODS

Genomic DNA was extracted from peripheral blood cells of 137 GD patients and 189 control subjects. Cytokine gene polymorphisms were analyzed by polymerase chain reaction and restriction fragment length polymorphism.

RESULTS

Genotype frequencies of TNF-alpha G-238A or G-308A between control and GD subjects were significantly different. Frequencies of the high TNF-alpha secreting alleles (-238*A and -308*A) and IL-10 -819*C allele were significantly increased in GD patients. No significant differences regarding IL-4 or IL-6 gene polymorphisms between GD patients and control subjects were found.

CONCLUSIONS

Our data demonstrated that TNF-alpha G-238A and G-308A genotypes were strongly associated with GD incidence.

Tumor necrosis factor alpha promoter polymorphism associated with increased susceptibility to secondary hemophagocytic lymphohistiocytosis in the Korean population

Secondary hemophagocytic lymphohistiocytosis (HLH) can be associated with various diseases including infections and lymphoma. The clinical findings of HLH can be explained by an increased production of cytokines such as tumor necrosis factor alpha (TNF-alpha). As not all the patients with infection or lymphoma have secondary HLH, we investigated the relationship between susceptibility to secondary HLH and TNF-alpha promoter polymorphisms to identify genetic factors of secondary HLH. We determined the alleles of four promoter sites (-1031/-857/-308/-238) of TNF-alpha gene by using Taqman-based allelic discrimination assays in the 66 Korean patients with secondary HLH and 100 healthy Korean controls. We found that the frequency of the TNF-alpha -1031C allele, which is associated with higher-plasma TNF-alpha levels, was enriched in patients with secondary HLH compared with healthy controls (OR=2.00, 95% CI 1.20-3.30, P=0.007). In haplotype analysis of TNF-alpha polymorphisms, the haplotype H6 (CTGG) was detected only in the patient group, and the haplotype group (H2 or H5 or H6) including TNF-alpha -1031C allele was overexpressed in secondary HLH patients (OR=2.52, 95% CI 1.33-4.77, P=0.004). These results suggested that TNF-alpha -1031C allele and its associated haplotypes in Koreans may enhance susceptibility to secondary HLH.

Haplotyping of TNFalpha gene promoter using melting temperature analysis: detection of a novel -856(G/A) mutation

Tumor necrosis factor alpha (TNFalpha) is a potent cytokine with a wide range of pro-inflammatory activities and plays a critical role in the pathogenesis of a number of infectious, inflammatory, autoimmune, and metabolic diseases. We determined four single-nucleotide polymorphisms (SNPs), -1031(C/T), -863(C/A), -857(C/T), and -308(G/A) in the TNFalpha promoter region using melting temperature analysis, among 1451 geriatric autopsy samples. Two adjacent SNPs, -863(C/A) and -857(C/T), were directly assayed by a single probe reaction, which correctly determined three of four expected haplotypes. Sequence confirmation related that the most rare haplotype (8/2902 chromosomes, frequency: 0.26%) contains a novel mutation of -856(G/A), instead of the predicted haplotype. These results indicate that melting temperature analysis provides a robust method to determine the polymorphisms in the TNFalpha promoter.