CT60 single nucleotide polymorphism of the CTLA-4 gene is associated with susceptibility to Graves' disease in the Taiwanese population

Graves' disease (GD) is an autoimmune disease but the underlying etiology has not been completely elucidated. Genetic susceptibility has been believed to play a major role. Recent studies showed that the CT60 single nucleotide polymorphism (SNP), which is in the 3'-noncoding region of the CTLA-4 gene, is strongly associated with some immune-mediated diseases. The aim of this study was to test for association between GD susceptibility and polymorphisms of CTLA-4 (ie, the CT60 SNP and the exon 1 +49 SNP) in the Taiwanese population. Our results demonstrate significant differences in the frequencies of the genotypes and alleles between 107 GD patients and 101 control subjects in the CT60 and exon 1 +49 SNPs (p <0.05). Significant differences in phenotypes were only found for CT60 SNP (78.4% vs 67.8% between patients and controls; chi2 = 3.93, p = 0.047). Furthermore, we found that the G/G genotype of both CT60 and exon 1 +49 was associated with increased risk for GD (p = 0.022, OR = 1.97). Significant linkage disequilibrium was found between the CT60 SNP and the exon 1 +49 SNP in both GD patients and control subjects (D' = 1.00). Because of tight linkage disequilibrium, a combination of these SNPs enhanced the role of the CTLA-4 gene in GD. The frequency of the disease-susceptible G allele of CT60 was comparable to that in Japanese and higher than in Caucasians. In conclusion, we provide evidence that CT60 SNP is associated with susceptibility to GD in the Taiwanese population.     

Association of the CTLA4 3' untranslated region polymorphism with the susceptibility to rheumatoid arthritis

Cytotoxic T-lymphocyte antigen 4 (CTLA4) gene polymorphism located in the 3' untranslated region (UTR) was investigated in 141 Spanish patients (38 men and 103 women) with rheumatoid arthritis (RA) and in 194 ethnically-matched healthy controls. Twenty alleles having different numbers of (AT) repeats (from 7 to 32) were found in this population. (AT)7 and (AT)16 were the most frequent alleles, and accounted for almost two-thirds of the allelic frequency in the control population. Consequently, alleles were assigned as L (large: 16 or more AT repeats) or S (short: less than 16 AT repeats). When the L/S distribution in patients and controls were compared, an increase of L alleles was observed among patients (49.9% vs. 39.7%; p = 0.02; p(c) = 0.04, odds ratio [OR] = 1.46; 95% confidence interval [CI], 1.06-2.01). Hence, the frequency of S alleles was decreased among patients (51.1% vs. 60.3%; p = 0.02; p(c) = 0.04; OR = 0.69; 95%CI, 0.50-0.95). Moreover, a statistically significant decrease in the frequency of S/S individuals was observed among RA patients (27.7% versus 40.7%; p = 0.01; p(c) = 0.03; OR = 0.56; 95%CI, 0.34-0.91). These differences were irrespective of the HLA "shared epitope" (SE) status, and were observed similarly among SE+ as well as among SE- patients. After combining these data with other reported previously by us, from studies of CTLA4 49 (A/G) and -318 (C/T) polymorphisms, we conclude that the strongest association between CTLA4 gene polymorphisms and RA susceptibility occurs with the 3' UTR polymorphism.     

High incidence of CTLA-4 AA (CT60) polymorphism in renal cell cancer

Polymorphism in genes encoding T-cell regulatory proteins and cytokines may influence inflammation and cancer development via regulation of antitumor immune response. In the current study we analyzed genotypic frequencies of cytotoxic T-lymphocyte antigen-4 (CTLA-4)/CT60, CTLA-4/A49G, interleukin (IL)-4, and IL-10 polymorphisms in 117 renal cell carcinoma patients, 96 patients with colorectal cancer, and 196 healthy controls to test for an association between polymorphism in these genes and the risk of renal and colon cancer in a Spanish group of patients. In the case-control study, DNA samples from cancer patients and controls were analyzed using a TaqMan single nucleotide polymorphism genotyping assay. The distribution of IL-4 and IL-10 polymorphisms was similar between renal cancer patients and controls. However, a higher incidence of CTLA-4/CT60-AA genotype (p = 0.005; odds ratio (OR)= 2.12 with 95% confidence interval (CI): 1.28-3.50) and CTLA-4/A49G-AA (p = 0.022; OR = 1.76 with 95% CI: 1.11-2.80) genotype was observed in renal cancer patients than in controls. In addition, we observed a positive correlation between the AA genotype in both CTLA-4 polymorphisms and RCC grade, suggesting a role for the CTLA4 gene in tumor development. Therefore, our data suggest the CTLA-4 gene may be a candidate as a renal adenocarcinoma susceptibility gene, but does not play an important role in colon cancer.     

CTLA-4基因启动子区单核苷酸多态性与特发性扩张型心肌病的关联研究

目的探讨特发性扩张型心肌病（idiopathic dilated cardiomyopathy，IDC）患者细胞毒性T淋巴细胞相关抗原-4（cytotoxic T lymphocyte assoccated antigen 4，CTLA-4）表达状况及由CTLA-4基因启动子区单核苷酸多态性（single nucleotide polymorphism，SNP）导致的不同遗传易感性机制。方法采用限制性片段长度多态性分析151例IDC患者，120名正常健康人CTLA-4基因启动区-1772、-1661及-318位点SNP；免疫酶联吸附测定法检测血清sCTLA-4、干扰素-7及白介素-4水平；综合分析CTLA-4启动区基因型、等位基因频率及与sCTLA-4、干扰素-γ／白介素一4的相关性。结果IDC患者sCTLA-4水平与CTLA一4基因启动区SNP相关，携带-1772T／C变异者sCTLA-4表达增高。-1772TC基因型频率在IDC组尤其低射血分数亚组显著高于对照组，IDC组-1661G和-1661GG频率显著降低，具有-1772TC-1661AA及-1772TC-1661AG单倍型IDC患者sCTLA-4显著升高。结论IDC患者CTLA-4表达异常，CTLA-4基因启动区-1772C／T和-1661A／GSNP与IDC遗传易感性相关。-1772T／C变异可能影响CTLA-4基因剪接，干扰蛋白表达和功能，阻止负性调节信号传递而导致对IDC的易感。     

广东人汉族群CTLA-4基因外显子1多态性与Graves病的相关性

目的探讨CTLA-4基因外显子1多态性与广东地区汉族人群Graves病的关系。方法以PCR-RFLP技术观察100名健康人与100例Graves病(GD)患者细胞毒性T淋巴细胞相关抗原4(CTLA-4)基因外显子1的多态性。结果提示GD患者的CTLA-4外显子1的G49等位基因频率较正常对照组显著增高(P<0.01)。结论CTLA-4基因可能是广东地区汉族人群中GD的易感候选基因。     

Association studies of the IL-23R gene in autoimmune thyroid disease in the Japanese population

Autoimmune thyroid diseases (AITDs), including Graves' disease (GD) and Hashimoto's thyroiditis (HT), are caused by interplays of genetic factors and environmental triggers. Interleukin-23 and its receptor (IL-23R) guide T cells towards the Th17 phenotype. IL-23R single nucleotide polymorphisms (SNPs) have been shown to be associated with several autoimmune diseases, including Crohn's disease and rheumatoid arthritis, and Graves' ophthalmopathy (GO) in Caucasians. To determine whether variants in the IL-23R gene are associated with AITDs in Japanese, 464 Japanese AITD patients (290 with GD, 174 with HT) and 179 matched Japanese control subjects were genotyped for four SNPs spanning the IL-23R gene. SNPs rs11209026 and rs7530511 were genotyped using TaqMan allelic discrimination assays and SNPs rs2201841 and rs10889677 were genotyped using a fluorescent-based restriction fragment length polymorphism method. Case-control association studies were performed using the χ² and Fisher's exact tests with Yates correction. Of the four SNPs rs11209026 was non-polymorphic in our dataset. The other three SNPs were not associated with GD or GO or HT in our Japanese population. These results suggest that the IL-23R gene is associated with AITDs only in a specific ethnic group.     

A single nucleotide polymorphism in the 5' untranslated region of the EGF gene is associated with occurrence and malignant progression of gastric cancer.

OBJECTIVE: Epidermal growth factor (EGF) has many biological functions and plays an important role in the progression of various tumors including gastric cancer. An A-G single nucleotide polymorphism (SNP) at position 61 in the 5'-untranslated region (UTR) of the EGF gene has recently been reported to be associated with different levels of EGF production. We examined whether this polymorphism is correlated with the development and malignant phenotypes of gastric cancer. METHODS: The study population included 200 gastric cancer patients and 230 healthy control subjects. The SNP in the 5'-UTR of the EGF gene was analyzed by polymerase chain reaction-restriction fragment length polymorphism. RESULTS: The A allele was significantly less frequent in patients than in controls (p = 0.01). Individuals with the A/A or A/G genotype showed a significantly lower risk of gastric cancer than those with the G/G genotype [adjusted odds ratio (OR) = 0.56], whereas the same genotypes were associated with malignant progression of this cancer, e.g. deeper tumor invasion, increased lymph node metastasis and advanced clinical stage, and histological classification in gastric cancer patients (adjusted OR = 1.80, 1.98, 2.26 and 1.89, respectively). CONCLUSIONS: Our findings suggest that the A-G polymorphism of EGF is involved not only in the occurrence but also in the malignant progression of gastric cancer.     

Association of single nucleotide polymorphisms in the IL-18 gene with sarcoidosis in a Japanese population

Interleukin-18 (IL-18) and interleukin-12 (IL-12) synergistically stimulate interferon-gamma (IFN-gamma) production from Th1 cells. The levels of serum IL-18 and IFN-gamma and bronchoalveolar lavage fluid IL-18 were elevated in patients with sarcoidosis. The polymorphisms of the IL-18 gene may play a possible role in expression regulation of the gene. We investigated the roles of the polymorphisms in the development of sarcoidosis. We examined two single nucleotide polymorphisms of the IL-18 gene in 119 patients with sarcoidosis and 130 healthy control subjects. Our results showed that the frequency of sarcoidosis patients with the CA genotype at position -607 was significantly higher than that with the AA genotype (OR = 2.200) and a significantly higher proportion of patients had the C allele at -607 compared with that of the controls (OR = 2.123). No significant differences were seen in the distribution of the genotypes or phenotype frequencies at position -137. There was no specific organ involvement associated with a certain genotype or phenotype. In IL-18 gene polymorphisms, the C allele at position -607 might be a genetic risk factor for sarcoidosis in this Japanese population.     

CTLA-4 (CD152) gene polymorphism at position 49 in exon 1 in Graves' disease in a Polish population of the Lower Silesian region

INTRODUCTION: Graves' disease ((GD)is an autoimmune disease believed to be caused by a combination of environmental and genetic factors. The gene encoding cytotoxic T lymphocyte-associated antigen-4 (CTLA-4)is one of the candidate genes for conferring susceptibility to thyroid autoimmunity. he aim of the study was to investigate the association between the exon 1 CTLA-4 gene polymorphism A(49)G and susceptibility to GD and Graves ' ophthalmopathy (GO)as well as its severity in a Polish population of the Lower Silesia region. MATERIALS AND METHODS: We analyzed the A(49)G exon 1 CTLA-4 gene polymorphism in 99 unrelated Polish patients with GD, of whom 50 had clinically evident GO (NOSPECS class III and higher), and 154 matched healthy subjects from the Lower Silesia region. Genomic DNA was isolated from whole frozen blood using the NucleoSpin Blood kit. A/G transition was genotyped by polymerase chain reaction followed by labeling with the SnaPshot kit of PE Applied Biosystems and detected using an ABI PRISM 310 capillary genetic analyzer. RESULTS: The distribution of CTLA-4 exon 1 A(49)G enotype, allele, and phenotypic frequencies did not differ between patients with GD and healthy subjects. There was a significantly lower frequency of the AA genotype in the group of patients with clinically evident GO than in patients without severe GO (22% vs. 43%; p=0.02, OR=2.6). CONCLUSIONS: Our results showed that the AA genotype in patients with GD is associated with a lower risk of GO severity.     

CTLA-4 (CD152) and its involvement in autoimmune disease

Autoimmune diseases (AID) are inherited as complex genetic diseases. Different Autoimmune diseases have been found to cluster in families and are believed to share some common etiological factors. With the exception of major histocompatibility complex (MHC) genes contributing susceptibility to these diseases have been difficult to identify. CD152 has emerged as one such candidate unifying several autoimmune diseases. We here review the evidence that CD152 constitutes a general susceptibility factor for multiple autoimmune diseases and discuss how CD152 and other co-stimulatory pathways may contribute to autoimmune pathogenesis.     

CTLA-4 (CD152) and its involvement in autoimmune disease

Autoimmune diseases (AID) are inherited as complex genetic diseases. Different Autoimmune diseases have been found to cluster in families and are believed to share some common etiological factors. With the exception of major histocompatibility complex (MHC) genes contributing susceptibility to these diseases have been difficult to identify. CD152 has emerged as one such candidate unifying several autoimmune diseases. We here review the evidence that CD152 constitutes a general susceptibility factor for multiple autoimmune diseases and discuss how CD152 and other co-stimulatory pathways may contribute to autoimmune pathogenesis.     

A single nucleotide polymorphism in the 3'-untranslated region of MyD88 gene is associated with Buerger disease but not with Takayasu arteritis in Japanese

Buerger disease (BD) and Takayasu arteritis (TA) are rare vascular disorders. Although their etiology and pathogenesis have not been elucidated, several studies have suggested the involvement of innate immunity. Myeloid differentiation primary-response protein 88 (MyD88) is a key signaling adaptor for all Toll-like receptors, which have a central role in innate immunity. In the present study, we evaluated the association of MyD88 with BD and TA. We conducted case-control studies in Japanese populations composing of 131 BD cases, 90 TA cases and 270 healthy controls to be genotyped for a single nucleotide polymorphism rs7744 A>G in the 3'-untranslated region of MyD88 gene. The frequency of GG genotype was significantly lower in the BD patients than in the controls (6.9 vs 15.9%, P=0.011, odds ratio=0.39, 95% confidence interval; 0.19, 0.81), although there was no significant difference in the genotype frequencies between the TA patients and controls. It was suggested that MyD88 may confer resistance to BD in Japanese. Because this is the first report of the association between MyD88 and BD, replication studies in other cohorts are required.     

CTLA-4 gene polymorphism and its association with Graves' disease in the Lebanese population.

Graves' disease is an organ-specific autoimmune disease that has a female predominance. It is probably the result of a complex interaction of genetic and environmental factors. This disease is characterized by immune system activation, evidenced by elevated serum thyroid-specific autoantibodies and lymphocytic infiltration of the target organ (the thyroid gland), associated with raised levels of circulating activated T lymphocytes. Several reports have demonstrated genetic linkage and association between the genetic markers of the CTLA-4 gene on chromosome 2q33 and Graves' disease. In order to confirm this association in the Lebanese population, a bi-allelic A/G polymorphism at position 49 of CTLA-4 exon 1 was studied in 34 patients with Graves' disease, and in 38 healthy individuals, using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. The results showed a significant increase in allele and genotype frequencies in patients with Graves' disease compared to controls. This suggests that the CTLA-4 gene might play a role in the development of Graves' disease in the Lebanese population.     

Analysis of the CTLA-4, CD28, and inducible costimulator (ICOS) genes in autoimmune thyroid disease

The cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) gene on 2q33 is associated with autoimmune thyroid diseases (AITDs). Our earlier study in 56 families showed linkage of 2q33 to the presence of thyroid antibodies (TAbs). The goals of this study were to confirm the linkage of the 2q33 region to TAbs, to fine map this region, and study the ICOS gene. We performed a linkage study in an expanded data set of 99 multiplex AITD-TAb families (529 individuals). The highest two-point LOD score of 2.9 was obtained for marker D2S325 on 2q33. To fine map this locus, we genotyped 238 Caucasian AITD patients and 137 controls for five additional markers in the linked locus, which contained the CTLA-4, CD28, and ICOS genes. The A/G single-nucleotide polymorphism at position 49 of CTLA-4 was associated with AITD (P=0.01, OR=1.5), while markers inside CD28 and ICOS were not. Functional studies have shown that the G allele was associated with reduced inhibition of T-cell proliferation by CTLA-4. We concluded that: (1) the AITD gene in the 2q33 locus is the CTLA-4 gene and not the CD28 or ICOS genes; and (2) the G allele is associated with decreased function of CTLA-4.     

TLR4基因多态性在中国人群中的初步研究

目的检测中国人Toll样受体4(Toll—like receptor 4．TLR4)基因调控区和编码区的单核苷酸多态性(single nucleotide polymorphisms，SNPs)．寻找TLR4基因的遗传标记。方法采用直接测序的方法检测基因的5′区、编码区、部分内含子区和3′区，以确定中国人群中TLR4基因SNP的位置和类型，并用聚合酶链反应-限制性片段长度多态性对重庆汉族样本进行了抽样调查。结果在4．98kb的测序范围内，发现5个新的SNP，3个位于5′区．2个位于3′非翻译区。在重庆地区汉族样本中．两个高频分布SNP的等位基因频率分别是0．266和0．404。结论在TLR4基因新发现的两个高频多态性位点在我国人群中比较常见，可以作为关联分析的遗传标记。     

Association between type 1 diabetes and polymorphism of the CTLA-4 gene in a Tunisian population]

Susceptibility to type 1 diabetes mellitus is strongly associated with particular HLA class II alleles. However, non HLA genetic factors are likely to be required for the development of disease. The candidate genes include the cytotoxic T lymphocyte associated 4 (CTLA-4) located on chromosome 2q33 and designated (IDDM12), which encodes a cell surface negative signal T molecule providing for activation. We investigated CTLA-4 exon 1 dimorphism in 74 type 1 patients and a control group of 48 healthy subjects from Tunisia using two methods PCR (polymerase chain reaction) allele specific and polymerase chain reaction restriction fragment length polymorphism (PCR RFLP). The CTLA-4/G allele was found on 68.9% in type 1 patients as compared to 51.02% in controls (p = 0.002), mostly in homozygous from 43.24% versus 22.45% (p = 0.0058). This results indicate that CTLA-4/G allele was significantly associated with predisposition to type 1 diabetes in our group from Tunisian population.