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PubMed2004

Functional polymorphisms in the sigma1 receptor gene associated with alcoholism.

BACKGROUND: Sigma1 receptors are involved in the pathogenesis of drug abuse. Two polymorphisms (GC-241-240TT and Gln2Pro) in the sigma1 receptor gene (SIGMAR1) have been identified. To investigate the role of SIGMAR1 in conveying susceptibility to alcoholism, we performed a functional analysis of polymorphisms in the SIGMAR1 and a case-control study. METHODS: We initially screened for polymorphisms in the 5'-upstream region. The effects of the polymorphisms on transcriptional activity were determined using a gene reporter assay. The distribution of SIGMAR1 polymorphisms was analyzed in 307 alcoholic and 302 control subjects. RESULTS: A novel T-485A polymorphism was identified. The transcriptional activity of the A-485 allele and the TT-241-240 allele was significantly reduced compared with that of the T-485 allele and the GC-241-240 allele. The frequencies of the A-485 allele (chi2=5.575, df=1, p=.0205) and the TT-241-240/Pro2 haplotype (chi2=21.464, df=1, p<.0001) were significantly higher in control subjects compared with alcoholic subjects. The T-485A and the GC-241-240TT may be functional polymorphisms, and the A-485 allele and TT-241-240/Pro2 haplotype are possible protective factors for the development of alcoholism.

Adult↗

PubMed2006

Polymorphisms of the glucocorticoid receptor gene and major depression.

BACKGROUND: The most consistent biological finding in patients with depression is a hyperactivity of the hypothalamic-pituitary-adrenal (HPA)-axis, which might be caused by impaired glucocorticoid signaling. Glucocorticoids act through the glucocorticoid receptor (GR) for which several polymorphisms have been described. The N363S and BclI polymorphisms have been associated with hypersensitivity to glucocorticoids, whereas the ER22/23EK polymorphism is related to glucocorticoid resistance. METHODS: We studied whether the susceptibility to develop a depression is related to these polymorphisms by comparing depressive inpatients (n = 490) and healthy control subjects (n = 496). Among depressed patients, we also investigated the relation between GR variants and dysregulation of the HPA-axis, as measured by the combined dexamethasone suppression/corticotropin-releasing hormone (CRH)-stimulation test, clinical response to antidepressive treatment, and cognitive functioning. RESULTS: Homozygous carriers of the BclI polymorphism and ER22/23EK-carriers had an increased risk of developing a major depressive episode. We found no genetic associations with functional HPA-axis measures in depressed patients. The ER22/23EK-carriers, however, showed a significantly faster clinical response to antidepressant therapy as well as a trend toward better cognitive functioning during depression. CONCLUSIONS: The BclI and ER22/23EK polymorphisms were associated with susceptibility to develop major depression. In addition, the ER22/23EK polymorphism is associated with a faster clinical response to antidepressant treatment. These findings support the notion that variants of the GR gene might play a role in the pathophysiology of a major depression and can contribute to the variability of antidepressant response.

Adult↗

PubMed2004

Association of plasma folate, plasma total homocysteine, but not methylenetetrahydrofolate reductase C667T polymorphism, with bone mineral density in postmenopausal Iranian women: a cross-sectional study.

Polymorphisms of methylenetetrahydrofolate reductase (MTHFR) have been well documented to cause hyperhomocysteinemia, and recent studies suggest an association of C677T mutation of methylenetetrahydrofolate reductase with low bone mineral density (BMD). In this study, the association of plasma total homocysteine (Hcy), plasma folate, and vitamin B12 as well as methylenetetrahydrofolate reductase C667T polymorphism with bone mineral density at neck of femur and lumbar spine in 271 postmenopausal Iranian women was investigated. Bone mineral density was measured by dual-energy X-ray absorptiometry. Restriction fragment length polymorphism was used for genotyping the methylenetetrahydrofolate reductase polymorphism. Plasma total homocysteine, plasma folate, and vitamin B12 were also determined. The bone mineral densities at the neck of femur and lumbar spine together with other clinical characteristics among methylenetetrahydrofolate reductase genotypes (CC, CT, and TT) were examined. Bone mineral densities at both neck of femur (r = -0.18, P = 0.003) and lumbar spine (r = -0.16, P = 0.01) were significantly and negatively correlated with the logarithm of plasma total homocysteine. Bone mineral density at the lumbar spine was also significantly and positively associated with plasma folate (r = 0.14, P = 0.02). However, no correlation between methylenetetrahydrofolate reductase polymorphism with bone mineral density at neck of femur (r = -0.01, P = 0.81) and lumbar spine (r = -0.04, P = 0.51) was observed. The negative association of plasma total homocysteine with bone mineral density was no longer significant when adjusted for folate and vitamin B12. Plasma folate and age were the main predictors of plasma total homocysteine explaining 15.3% and 5.2% of the variance of plasma total homocysteine, respectively. Methylenetetrahydrofolate reductase polymorphism, however, was not associated with plasma folate (r = 0.086, P = 0.17) or vitamin B12 (r = 0.05, P = 0.4). Plasma folate was one of the main predictors explaining 3.0% and 1.7% of variance of the bone mineral density at femoral neck and lumbar spine, respectively. Results from this study suggest hyperhomocysteinemia as a result of folate deficiency, but not methylenetetrahydrofolate reductase polymorphism, is independently associated with low bone mineral density and may contribute to the pathogenicity of osteoporosis in postmenopausal Iranian women.

Aged↗

PubMed2005

Micronuclei in EM9 cells expressing polymorphic forms of human XRCC1.

X-ray repair cross-complementing gene 1 (XRCC1) is involved in base excision repair (BER) through interaction with other BER enzymes, and polymorphisms in XRCC1 appear to increase the risk of various cancers. We evaluated how three XRCC1 polymorphisms, Arg194Trp, Arg280His and Arg399Gln, affect the extent of DNA damage and repair using the micronucleus assay. XRCC1 cDNAs containing the wild-type sequence and the three polymorphisms were overexpressed in EM9 cells, which lack the full sequence needed to perform XRCC1 functions. Normal human XRCC1 cDNA corrected the defect in EM9 cells. Only XRCC1 cDNA containing the Arg399Gln polymorphism did not fully correct the DNA repair defect in EM9 cells. These results indicate that the Arg399Gln polymorphism, but not the Arg194Trp or Arg280His polymorphism, influences the ability of XRCC1 to repair DNA. This study may provide a model that can be used to evaluate the functional significance of polymorphisms in DNA repair genes.

Animals↗

PubMed2006

Platelet glycoprotein polymorphisms: risk, in vivo expression and severity of atherothrombotic stroke in Chinese.

BACKGROUND: Polymorphisms in platelet glycoprotein (GP) receptors Ia, Ib and IIIa may be heritable risk factors for platelet-dependent thrombosis leading to death. The precipitation of stroke by occlusive thrombi has led to the investigation of the platelet surface GP receptors, that are involved in critical steps in the activation of platelets. Three polymorphisms in the GP Iba gene and one in each of GPIIIa, GP Ia were selected based on the evidence of functional effects on structure or expression as candidates for risk. We also determined whether these polymorphisms were associated with in vivo expression levels of platelet GP receptors and the severity of the neurological deficit. METHODS: A Chinese hospital-based case-control study was conducted with 119 cases of atherothrombotic stroke and 166 age and sex matched controls. Genotyping was performed on lymphocyte DNA by standard methods and platelet GP expression levels were measured by flow-cytometry. RESULTS: Allele and genotype frequencies of the GP receptor polymorphisms differ considerably between ethnic populations. We found the D allele of the GP Iba VNTR polymorphism was significantly associated with atherothrombotic stroke in our Chinese cohort, however we did not find a relationship among these polymorphisms, the expression levels of GP receptors and severity of the neurological deficit. CONCLUSIONS: In our Chinese cohort the D allele of the GP Iba VNTR polymorphism is associated with atherothrombotic stroke. The number of VNTR repeats alters the length of amino acid sequence, which might affect the structure and function of this receptor.

Adult↗

PubMed2006

Influences of proinflammatory and anti-inflammatory cytokine polymorphisms on eradication rates of clarithromycin-sensitive strains of Helicobacter pylori by triple therapy.

BACKGROUNDS AND AIMS: Polymorphisms of proinflammatory cytokines, such as interleukin (IL) 1beta and tumor necrosis factor (TNF) alpha, are associated with individual differences in gastric mucosal inflammation and acid inhibition in response to Helicobacter pylori infection. We investigated whether inflammation-related cytokine polymorphisms would influence the eradication rates of H pylori by a triple-therapy regimen. METHODS: Three hundred sixty patients infected with clarithromycin-sensitive strains of H pylori were genotyped for IL1B -511, IL1RN, TNFA -857/-863/-1,031, IL10 -1,082/-819/-592, and CYP2C19 and underwent triple therapy for 1 week with a proton pump inhibitor (20 mg omeprazole, 30 mg lansoprazole, or 10 mg rabeprazole) twice daily, 400 mg clarithromycin twice daily, and 750 mg amoxicillin (INN, amoxicilline) twice daily. The influences of the previously mentioned polymorphisms on the eradication rates were analyzed. RESULTS: The intention-to-treat-based total eradication rate was 83.6% (301/360). The logistic regression analysis revealed that polymorphisms of CYP2C19 and IL1B -511 were independently associated with the eradication rates, but other cytokine polymorphisms were not associated with these rates. The eradication rates in patients with IL1B -511 C/C, C/T, and T/T genotypes were 72.2% (70/97), 87.7% (164/187), and 88.2% (67/76), respectively (P = .0017). When patients were stratified by CYP2C19 genotype status, IL1B -511 genotype-dependent differences in eradication rates were observed in homozygous extensive metabolizers (EMs) but not in heterozygous EMs and poor metabolizers of CYP2C19. The eradication rate in homozygous EM patients with the IL1B -511 C/C genotype was quite low (51.1% [22/43]). CONCLUSIONS: IL1B -511 polymorphism, but not IL1RN, TNFA, or IL10 polymorphism, is one of the determinants of triple therapy for clarithromycin-sensitive strains of H pylori in CYP2C19 homozygous EMs.

Anti-Bacterial Agents↗

PubMed2005

Predicting drug response and toxicity based on gene polymorphisms.

The sequencing of the human genome has allowed the identification of thousands of gene polymorphisms, most often single nucleotide polymorphims (SNP), which may play an important role in the expression level and activity of the corresponding proteins. When these polymorphisms occur at the level of drug metabolising enzymes or transporters, the disposition of the drug may be altered and, consequently, its efficacy may be compromised or its toxicity enhanced. Polymorphisms can also occur at the level of proteins directly involved in drug action, either when the protein is the target of the drug or when the protein is involved in the repair of drug-induced lesions. There again, these polymorphisms may lead to alterations in drug efficacy and/or toxicity. The identification of functional polymorphisms in patients undergoing chemotherapy may help the clinician prescribe the optimal drug combination or schedule and predict with more accuracy the response to these prescriptions. We have recorded in this review the polymorphisms that have been identified up till now in genes involved in anticancer drug activity. Some of them appear especially important in predicting drug toxicity and should be determined in routine before drug administration; this is the case of the most common variations of thiopurine methyltransferase for 6-mercaptopurine and of dihydropyrimidine dehydrogenase for fluorouracil. Other appear determinant for drug response, such as the common SNPs found in glutathione S-transferase P1 or xereoderma pigmentosum group D enzyme for the activity of oxaliplatin. However, confusion factors may exist between the role of gene polymorphisms in cancer risk or overall prognosis and their role in drug response.

Cytochrome P-450 Enzyme System↗

PubMed2004

Polymorphisms in candidate genes for type 2 diabetes mellitus in a Mexican population with metabolic syndrome findings.

The metabolic or insulin resistance syndrome, characterized by hypertension, dyslipidemia, glucose intolerance and hyperinsulinemia, may have genetic determinants. The insulin gene (INS), insulin receptor gene (INSR) and insulin receptor substrate 1 gene (IRS1) have been proposed as candidate genes. We examined eight polymorphisms in these genes in 163 individuals from Yucatan, Mexico; this population has a high prevalence of obesity, type 2 diabetes mellitus and dyslipidemia. Subjects were evaluated for body mass index (BMI) and blood pressure. Blood samples were collected to determine glucose, insulin, triglycerides and cholesterol levels, as well as for DNA isolation. Restriction fragment length polymorphisms in INS, INSR and IRS1 were identified by polymerase chain reaction and digestion with selected restriction enzymes. Among the eight polymorphisms analyzed, the PstI polymorphism in INS was significantly associated with hypertriglyceridemia and with the presence of at least one abnormality related to the metabolic syndrome (P=0.007 and 0.004, respectively). The MaeIII polymorphism in INS was associated with fasting hyperinsulinemia (P=0.045). In multilocus analyses including both INS polymorphisms, significant associations were seen with hypertriglyceridemia (P=0.006), hypercholesterolemia (P=0.031) and with presence of at least one metabolic abnormality (P=0.009). None of the polymorphisms in INSR or IRS1 was associated with any of these traits. These findings suggest that the insulin gene may be an important determinant of metabolic syndrome, and particularly of dyslipidemia, in this population.

Adolescent↗

PubMed2005

Relationships between promoter polymorphisms in the thymidylate synthase gene and mRNA levels in colorectal cancers.

Thymidylate synthase (TS) intratumoural expression may be a prognostic marker and predict outcome of 5-fluorouracil (5-FU)-based chemotherapy in colorectal cancer patients. The TS gene promoter enhancer region contains two different polymorphisms which can influence TS mRNA transcriptional and translational efficiency: a polymorphic tandem repeat sequence (2 or 3 repeats; 2R and 3R) and a single nucleotide polymorphism (SNP), G > C, within the second repeat of the 3R alleles. We studied the relationship between tumoural TS mRNA expression levels and TS gene polymorphisms in the colonic mucosa of 48 colorectal cancer patients. The 3R/3R genotype was characterised by higher TS mRNA levels in the tumour than the 2R/2R-2R/3R genotypes (P = 0.071). Regarding the relationship with the SNP polymorphism, a statistically significant difference in TS gene expression between the 3RG/3RG genotype and 2R/2R-2R/3RC-2R/3RG genotype subset was observed (P = 0.017). No statistically significant correlation was observed between experimental data and baseline clinical-pathological characteristics as well as clinical outcome in the relatively small patient series investigated. This is the first study reporting an association between the TS intra-repeat SNP and gene expression levels in colorectal cancer patients. These results suggest that in 3R/3R patients, the G > C polymorphism may be an important factor in determining TS mRNA expression levels, and warrant further investigation of the role of TS promoter polymorphisms as predictors of sensitivity to 5-FU-based chemotherapy in larger case series.

Adult↗

PubMed2006

Polymorphisms of interleukin-6, hepatic lipase and calpain-10 genes, and preeclampsia.

OBJECTIVE: We determined whether single nucleotide polymorphisms (SNPs) in interleukin-6 (IL-6), hepatic lipase (HL) and calpain-10 (CAPN-10) genes contribute to susceptibility to develop preeclampsia. STUDY DESIGN: The study involved 133 preeclamptic and 115 healthy pregnant women who were genotyped for the C-174G polymorphism in the IL-6 gene, the G-250A polymorphism in the HL gene and SNP 43 (G/A) in the CAPN-10 gene. The chi2-test was used to assess genotype and allele frequency differences between the preeclamptic and control groups. RESULTS: No significant differences were detected in genotype and allele distributions of the C-174G polymorphism in the IL-6 gene, between the preeclampsia and control groups (p=0.98 and 0.85, respectively). With respect to the G-250A polymorphism in the HL gene, the genotype and allele distributions were similar in both groups (p=0.64 and 0.48, respectively). The genotype and allele distributions of SNP 43 in the CAPN-10 gene also showed no statistical differences in the preeclampsia and control groups (p=0.73 and 0.45, respectively). CONCLUSIONS: The C-174G polymorphism in the IL-6 gene, the G-250A polymorphism in the HL gene and SNP 43 (G/A) in the CAPN-10 gene are unlikely to be major genetic factors predisposing Finnish women to preeclampsia.

Adult↗

PubMed2004

Association of male infertility with Pro185Ala polymorphism in the aryl hydrocarbon receptor repressor gene: implication for the susceptibility to dioxins.

OBJECTIVE: To examine whether Arg554Lys polymorphism in the gene for aryl hydrocarbon receptor (AHR) and/or Pro185Ala polymorphism in the gene for aryl hydrocarbon receptor repressor (AHRR) constitutes a susceptibility locus for dioxin-related male infertility. DESIGN: Association study of male infertility with polymorphisms. SETTING: National research institute and university hospitals. PATIENT(S): 123 Japanese men with azoospermia or severe oligozoospermia and 112 men with proven fertility. INTERVENTION(S): Polymorphism analysis. MAIN OUTCOME MEASURE(S): The allele and genotype frequencies between infertile men and controls. RESULT(S): The allele and genotype frequencies of the AHR polymorphism were comparable between infertile men and controls. By contrast, although the difference in the allele frequency of the AHRR polymorphism did not reach a significant level, the genotype frequency was statistically significantly different between the two groups of men. Furthermore, the statistical difference became more significant when the frequency was compared between the Pro/Pro genotype and the Pro/Ala plus Ala/Ala genotype. CONCLUSION(S): The Pro185Ala polymorphism in AHRR may constitute a susceptibility locus for dioxin-related male infertility. It appears that the negative feedback effect of AHRR on dioxin-related signaling is weaker for the proline allele than for the alanine allele, and that the hypomorphic function of the proline allele exerts a recessive adverse effect on male fertility.

Adult↗

PubMed2004

G protein polymorphisms do not predict weight loss and improvement of hypertension in severely obese patients.

Both the gene encoding the alpha subunit of G stimulatory proteins (GNAS1) and the beta3 subunit gene (GNB3) of G proteins are associated with obesity and/or hypertension. Moreover, the TT/TC825 polymorphism of GNB3 predicts greater weight loss than the CC825 polymorphism in obese patients (mean body mass index, 35 kg/m2) undergoing a structured nonpharmacologic weight loss program. Gastric banding enforces a low-calorie diet by diminishing the need for volitional adherence. It is unknown whether these polymorphisms predict the variable weight loss in patients after bariatric surgery. Three hundred and four severely obese patients (mean +/- SEM age, 42 +/- 1 years; 245 women and 59 men; mean +/- SEM body mass index, 43.9 +/- 0.3 kg/m2) followed prospectively for at least 3 years after surgery were genotyped for the GNB3 C825T, G814A, and GNAS1 T393 polymorphisms. All analyses were performed blinded to the phenotypic characteristics of the study group. Frequencies of polymorphisms were comparable to those previously published. No polymorphism studied predicted 3-year weight loss or was associated with high blood pressure in severely obese patients after gastric banding. Multivariate analysis of potentially confounding factors such as reoperation rate or use of sibutramine or orlistat revealed similar results (P > 0.1). Regardless of the mechanism(s) involved for these discordant findings, GNB3 C825T, G814A, and GNAS1 T393C polymorphisms do not seem to be reliable predictors of long-term weight loss.

Adult↗

PubMed2004

Genetics and biology of vitamin D receptor polymorphisms.

The vitamin D endocrine system is involved in a wide variety of biological processes including bone metabolism, modulation of the immune response, and regulation of cell proliferation and differentiation. Variations in this endocrine system have, thus, been linked to several common diseases, including osteoarthritis (OA), diabetes, cancer, cardiovascular disease, and tuberculosis. Evidence to support this pleiotropic character of vitamin D has included epidemiological studies on circulating vitamin D hormone levels, but also genetic epidemiological studies. Genetic studies provide excellent opportunities to link molecular insights with epidemiological data and have therefore gained much interest. DNA sequence variations, which occur frequently in the population, are referred to as "polymorphisms" and can have modest and subtle but true biological effects. Their abundance in the human genome as well as their high frequencies in the human population have made them targets to explain variation in risk of common diseases. Recent studies have indicated many polymorphisms to exist in the vitamin D receptor (VDR) gene, but the influence of VDR gene polymorphisms on VDR protein function and signaling is largely unknown. So far, three adjacent restriction fragment length polymorphisms for BsmI, ApaI, and TaqI, respectively, at the 3' end of the VDR gene have been the most frequently studied. Because these polymorphisms are probably nonfunctional, linkage disequilibrium with one or more truly functional polymorphisms elsewhere in the VDR gene is assumed to explain the associations observed. Research is therefore focussed on documenting additional polymorphisms across the VDR gene to verify this hypothesis and on trying to understand the functional consequences of the variations. Substantial progress has been made that will deepen our understanding of variability in the vitamin D endocrine system and might find applications in risk assessment of disease and in predicting response-to-treatment.

Chromosomes, Human, Pair 12↗

PubMed2006

Whole genome computational comparative genomics: A fruitful approach for ascertaining Alu insertion polymorphisms.

Alu elements are the most active and predominant type of short interspersed elements (SINEs) in the human genome. Recently inserted polymorphic (for presence/absence) Alu elements contribute to genome diversity among different human populations, and they are useful genetic markers for population genetic studies. The objective of this study is to identify polymorphic Alu insertions through an in silico comparative genomics approach and to analyze their distribution pattern throughout the human genome. By computationally comparing the public and Celera sequence assemblies of the human genome, we identified a total of 800 polymorphic Alu elements. We used polymerase chain reaction-based assays to screen a randomly selected set of 16 of these 800 Alu insertion polymorphisms using a human diversity panel to demonstrate the efficiency of our approach. Based on sequence analysis of the 800 Alu polymorphisms, we report three new Alu subfamilies, Ya3, Ya4b, and Yb11, with Yb11 being the smallest known Alu subfamily. Analysis of retrotransposition activity revealed Yb11, Ya8, Ya5, Yb9, and Yb8 as the most active Alu subfamilies and the maintenance of a very low level of retrotransposition activity or recent gene conversion events involving S subfamilies. The 800 polymorphic Alu insertions are characterized by the presence of target site duplications (TSDs) and longer than average polyA-tail length. Their pre-integration sites largely follow an extended "NT-AARA" motif. Among chromosomes, the density of Alu insertion polymorphisms is positively correlated with the Alu-site availability and is inversely correlated with the densities of older Alu elements and genes.

Alu Elements↗

PubMed2006

Polymorphism in the 5' upstream regulatory and 3' untranslated regions of the HLA-G gene in relation to soluble HLA-G and IL-10 expression.

The nonclassical human leukocyte antigen (HLA) class Ib gene HLA-G may be important for the induction and maintenance of immune tolerance between the mother and the semi-allogeneic fetus during pregnancy. Expression of HLA-G can influence cytokine and cytotoxic T-lymphocyte responses. Different HLA-G mRNA isoform expression patterns have been associated with HLA-G polymorphism, especially with a 14-bp insertion deletion polymorphism in the 3' untranslated region (3'UTR) of the HLA-G gene. A significantly high level of interleukin-10 (IL-10) secretion is observed in homozygous +14/+14-bp HLA-G peripheral blood mononuclear cells after lipopolysaccharide (LPS) stimulation. This study finds that polymorphism in the 5' upstream regulatory region (5'URR) of the HLA-G gene may also be implicated in differences in IL-10 secretion. However, this may also be due to linkage disequilibrium with the 14-bp polymorphism. A single-nucleotide polymorphism located -477 bp from the start site of exon 1 had a significant association with IL-10 concentrations but not after correction (p=0.011; pc=0.154). This polymorphism is located next to a heat shock element. Eighteen 5'-URR/3'-UTR HLA-G haplotypes were defined; one common homozygous genotype based on these haplotypes was significantly associated with a high IL-10 level after LPS stimulation compared to certain other genotypes. This study indicates that polymorphism in the 5'-URR of the HLA-G gene may have functional significance, although a new line of investigations is needed to elucidate these findings.

3' Untranslated Regions↗

PubMed2006

CTLA4 polymorphisms and ophthalmopathy in Graves' disease patients: association study and meta-analysis.

Studies in the past have clearly established that cytotoxic T-lymphocyte antigen-4 (CTLA4) is a susceptible gene for Graves' disease (GD). However, association studies between the CTLA4 exon-1 +49A/G polymorphism and the risk of developing Graves' ophthalmopathy (GO) in GD patients have revealed conflicting results. In this study, associations of two CTLA4 polymorphisms (+49A/G and CT60) with GD risk and GO susceptibility in GD patients were investigated in a Chinese population. In addition, a meta-analysis was performed to better assess the purported association between the +49A/G polymorphism and GO susceptibility in GD patients. Our results demonstrated that both the +49A/G and CT60 polymorphisms were associated with GD susceptibility in the Chinese population. No significant association with GO susceptibility in GD patients was confirmed regardless of which polymorphism was tested individually. Similarly, the meta-analysis results provided minimal evidence about the role of the +49A/G polymorphism and GO risk in GD patients. Interestingly, haplotypic analysis demonstrated different scenarios concerning the role of CTLA4 in GO susceptibility in the Chinese GD patients. We found that the +49A-CT60G haplotype was marginally statistically associated with the increased risk of GO in GD patients (OR = 1.63, 95%CI 1.00-2.64, p = 0.05). In conclusion, our results suggested that CTLA4 might be involved in the susceptibility to GD in the Chinese population. Although neither +49A/G nor CT60 polymorphism was associated with the risk of GO in GD patients, the haplotypic analysis provided some evidence about its role in GO susceptibility in the Chinese GD patients. We suggest that more association studies recruiting haplotypic analysis should be performed to investigate the role of CTLA4 gene in GO susceptibility in patients from different nations.

Adult↗

PubMed2005

Renin-angiotensin system and haemostasis gene polymorphisms and outcome after coronary artery bypass graft surgery.

BACKGROUND: Coronary artery bypass graft surgery is associated with a considerable 2-year mortality rate. Gene polymorphisms of the renin-angiotensin system may be associated with the risk of hypertension and cardiovascular disease. The angiotensin I-converting enzyme DD genotype has recently been identified as independent predictor of the outcome after coronary artery bypass graft surgery. Genetic factors of the clotting system may be related to the risk of myocardial infarction and restenosis after coronary interventions. The aims of the present study were to investigate whether gene polymorphisms of the renin-angiotensin system (angiotensinogen 235 M/T, angiotensin II type 1 receptor 1166 A/C) or the clotting system (glycoprotein IIIa PlA1/PlA2 and factor V Leiden 1691 G/A) are associated with the outcome after coronary artery bypass grafting. METHODS: A study population of 247 patients was followed-up 2 years after coronary artery bypass graft surgery. The primary end-point was total mortality. The secondary end-point was mortality from cardiac cause or the need for myocardial revascularization (percutaneous coronary interventions or recurrent surgery) during follow-up. Geno typing was performed by polymerase chain reaction- and restriction fragment length polymorphism-based techniques. RESULTS: An older age and the non-use of the internal mammary artery graft were identified as independent predictors of the primary end-point after coronary artery bypass grafting. A decreased left ventricular ejection fraction was an independent predictor for the secondary end-point. No association was found between any of the genetic factors and the outcomes after coronary artery bypass graft surgery in the main factor regression models. However, the angiotensin II type 1 receptor 1166 A/C gene polymorphism modulated the effects of age on the primary end-point, and the angiotensinogen 235 M/T gene polymorphism modulated the effects of age on the secondary end-point. CONCLUSION: We conclude that there are interactions between the angiotensin II type 1 receptor 1166 A/C as well as the angiotensinogen 235 M/T gene polymorphism and age with respect to the outcome after coronary artery bypass graft surgery. The glycoprotein IIIa PlA1/PlA2 and the factor V Leiden 1691 G/A gene polymorphisms were not associated with mid-term mortality or cardiac morbidity after coronary artery bypass grafting.

Adult↗

PubMed2005

A protective contribution of the Q allele of the R353Q polymorphism of the Factor VII gene in individuals with chronic stable angina?

BACKGROUND: Factor VII polymorphisms have been suggested in some studies to show an association with some aspects of coronary disease, and there is a known association between FVII levels and polymorphic variants in the gene. The aim of the study was to assess whether Factor VII polymorphism R353Q is associated with the extent of coronary artery disease in patients with chronic stable angina. METHODS AND RESULTS: There is evidence that Factor VII polymorphisms are markers of susceptibility to coronary artery disease (CAD), but two studies have suggested that there is no association between the degree of vessel disease and these polymorphisms. One of these studies did not exclude patients with unstable angina or MI. We therefore set up a prospective cohort study to determine Factor VIIa, VIIc and VIIAg levels, genotype for R353Q, lipid status, smoking history and the degree of vessel disease, in patients attending the hospital for routine day case angiography over a 20 month period. From 519 cases, 400 had no previous MI or revascularisation, including 153 with zero vessel disease, and were successfully genotyped: 9 (2%) QQ, 78 (20%) RQ and 313 (78%) RR. Compared with RR subjects, heterozygotes were 2.7 years older (95% CI: 0.3, 5.0; p=0.027), but were not significantly different regarding gender, cholesterol, extent of vessel disease or smoking history. If those with vessel disease were considered, then the heterozygotes were 3.5 years older than the RR homozygotes (95% CI: 0.6-6.4, p=0.016). There was a significant association between all measures of Factor VII and the R353Q polymorphism, with the Q allele associating with lower levels. There was no significant association between the degree of vessel disease and genotype. CONCLUSIONS: The degree of vessel disease as seen at day case angiography is independent of polymorphism status, but there appears nonetheless to be a moderate protective effect of the Q allele against stable angina, in that angiographic investigation occurs a few years later for RQ heterozygotes than RR homozygotes. The effect may be mediated by reduced levels of Factor VII.

Alleles↗