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PubMed2000

Genetic polymorphisms and coronary artery disease in the south of France.

Vascular disease is a multifactorial disease that involves atherosclerotic and thrombotic factors. Genetic polymorphisms have been associated with myocardial infarction and angina pectoris. The aim of the present study was to assess the relationship between some genetic polymorphisms and myocardial infarction (MI) or vasospastic angina pectoris in a population from southern France. Genetic polymorphisms of the renin angiotensin system (the D/I polymorphism of the ACE gene and the A1166C polymorphism of the angiotensin II type 1 receptor [AT1R]) and of haemostatic factors (the -675 4G/5G polymorphism of the plasminogen-activator inhibitor 1[PAI-1] gene, and the G to T common point mutation in exon 2, codon 34 of the Factor XIII A-subunit gene) were examined. We assessed the genotype distribution in consecutive coronary artery disease (CAD) patients with MI (n = 201) and vasospastic angina pectoris (n = 43) and in 244 healthy controls comparable in age, sex, body mass index and total cholesterol level. The genotype distribution of AT1R polymorphism was significantly different between controls and patients, the prevalence of the C allele carriers being higher in patients with MI after the age of 45 than in control individuals (61 vs 45%, p <0.01), leading to an odds ratio (OR) of 2 (CI: 1.2-3.4). When looking at the group of patients with vasospastic angina the difference was even higher (76 vs 45%, p <0.01) yielding an OR of 4.3 (CI: 1.4-17.4). Genotype distributions of ACE, PAI-1 and Factor XIII polymorphisms were similar in patients and in controls. This study is in favor of a role of ATIR gene polymorphism in myocardial infarction and vasospastic angina.

Adolescent↗

PubMed2000

Effect of allelic polymorphism of the B(1) and B(2) receptor genes on the contractile responses of the human umbilical vein to kinins.

The human genes corresponding to the two receptor (R) subtypes for bradykinin (BK)-related peptides, the B(1)R and B(2)R, are known to be polymorphic. The human isolated umbilical vein responds by contractions to stimulation by kinins via constitutive B(2)Rs and inducible B(1)Rs. Vascular rings from 100 different umbilical cords were submitted to a standardized protocol where E(max) values were obtained at 2 and 6 h of incubation, and EC(50) values were estimated at 6 h for the B(1)R agonist Sar-¿D-Phe(8)des-Arg(9)-BK; E(max) and EC(50) values were also obtained for the B(2)R agonist BK at 4 h. The genotype of each tissue donor was determined for two polymorphic sites in the B(1)R gene and three such sites in the B(2)R gene. The (-/-) genotype of a frequent insertion/deletion polymorphism of the B(2)R exon 1 was associated with increased contractile efficiency of the B(1)R agonist, Sar-¿D-Phe(8)des-Arg(9)-BK, but had no effect on BK-induced contractility. A B(2)R exon 2 polymorphism (C(181) --> T) selectively influenced the potency of BK (EC(50) higher when the T allele was present). The other polymorphisms studied were not found to affect kinin-induced contractility. Although most of the frequent polymorphic alleles of the kinin receptor genes are functionally neutral or determine functional alterations that are not detectable using the method used here, two B(2)R polymorphic sites (exon 1, exon 2) modestly influence function. As the exon 1 B(2)R polymorphism predicts the response of the B(1)R agonist, it may be in linkage disequilibrium with an unknown, functionally important polymorphism of the neighboring B(1)R gene.

Alleles↗

PubMed2000

Plasma nitric oxide concentrations and nitric oxide synthase gene polymorphisms in coronary artery disease.

BACKGROUND: Plasma NOx (nitrate and nitrite) is a stable end product of the vasodilator NO. Several polymorphisms in the endothelial constitutive NO synthase (ecNOS) gene have been reported, including the 4a/4b VNTR polymorphism in intron 4, the E298D mutation in exon 7, and the G10-T polymorphism in intron 23. The aims of this study were to examine plasma NOx in patients with coronary artery disease (CAD) and to assess the association between plasma NOx concentrations and the three ecNOS gene polymorphisms. METHODS: Plasma NOx was measured in samples from 128 healthy controls and from 110 CAD patients at least 2 months after myocardial infarction. Three genetic polymorphisms that are known or have been suggested to be associated with plasma NOx concentration were also analyzed by PCR-restriction fragment length polymorphism. RESULTS: Median plasma NOx was significantly higher (P <0.001) in CAD patients (95.9 micromol/L) than in controls (73.8 micromol/L). Furthermore, the median plasma NOx was significantly higher (P <0.001) in hypertensive CAD patients (116.0 micromol/L) than in controls and normotensive CAD patients (86.0 micromol/L). The G-allele frequency of the G10-T polymorphism in intron 23 was significantly higher in CAD patients than in controls. Other polymorphisms showed no differences in allelic frequencies among the control and CAD groups. In controls, individuals with the E298D mutation in exon 7 (136.1 micromol/L) showed significantly higher (P = 0.001) median plasma NOx than those without this mutation (64.5 micromol/L). CONCLUSIONS: Plasma NOx was higher in hypertensive CAD patients than in normotensive CAD patients and controls. The E298D polymorphism of the ecNOS gene was associated with increased plasma NOx. Further study is needed to understand the gene expression and enzyme activity of ecNOS and their association with genotypes.

Aged↗

PubMedDate not supplied

A C2077T polymorphism of the type B human natriuretic peptide receptor gene is not associated with myocardial infarction.

INTRODUCTION: We examined previously the genomic structure of the human natriuretic peptide receptor type B (hNPRB) gene and reported a C2077T polymorphism located in exon 11 of the gene. We now have studied the C2077T polymorphism in myocardial infarction [MI] patients and non-MI [control] subjects to evaluate the value of this polymorphism as a marker for MI. MATERIAL AND METHODS: 302 subjects (163 MI patients and 139 non-MI age-matched control subjects) were studied. PCR-restriction fragment length polymorphism analysis (PCR-RFLP) was developed to detect the C2077T transition. RESULTS: The distribution of C2077T polymorphism genotypes in the MI patients (CC:CT:TT, 47.2%:41.1%:11.7%) was not significantly different from that in the control patients (CC:CT:TT, 53.2%:40.3%:6.5%) (chi 2 = 2.73, p = NS). Allele frequencies of the C2077T polymorphism were f(C/T) 68.2%/31.8% in the MI group and 73.4%/26.6% in the control group. However, no association was found between this polymorphism and clinical diagnosis of MI. CONCLUSION: Our data indicate that the C2077T polymorphism is not a useful marker of the relation between the hNPRB gene and MI in the Japanese and variations of the hNPRB gene that may be in linkage disequilibrium with this polymorphism do not play a causative role in MI.

Aged↗

PubMed2001

The association between polymorphisms in the CYP17 and 5alpha-reductase (SRD5A2) genes and serum androgen concentrations in men.

Prospective studies suggest that prostate cancer risk may be increased in association with high serum concentrations of free testosterone and androstanediol glucuronide (A-diol-g). Polymorphisms have been identified in the 17-hydroxylase cytochrome P450 gene (CYP17) and the steroid 5alpha-reductase type II gene (SRD5A2), two genes that are involved in the biosynthesis and metabolism of androgens in men. The CYP17 MspA1 I polymorphism has been associated with increased prostate cancer risk, and the SRD5A2 V89L polymorphism has been associated with low A-diol-g in Asian men, a serum marker of 5alpha-reductase activity. The purpose of this study was to investigate the association between these two polymorphisms and serum sex hormone concentrations in 621 British men. In particular, we wanted to test the hypotheses that the A2 allele in the CYP17 gene is associated with increased serum testosterone concentrations, and the L allele in the SRD5A2 gene is associated with reduced A-diol-g concentrations. Mean hormone concentrations were evaluated in each genotype and adjusted for age and other relevant factors. We found no evidence that the CYP17 MspA1 I polymorphism was associated with higher testosterone levels. The L/L genotype of the SRD5A2 V89L polymorphism was associated with a 10% lower A-diol-g concentration, but this was not significant at the 5% level. However, the L/L genotype of the V89L polymorphism was associated with significantly lower concentrations of testosterone and free testosterone (by 12% and 16%, respectively) and an 8% higher sex hormone-binding globulin concentration. These results suggest that the CYP17 MspA1 I polymorphism is not associated with testosterone concentrations and that the SRD5A2 V89L polymorphism is not a strong determinant of A-diol-g concentration in Caucasian men.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗

PubMed2001

Human endothelial cell-derived nuclear proteins that recognise polymorphic DNA elements in the von Willebrand factor gene promoter include YY1.

Four common base-change polymorphisms have been found in the von Willebrand factor gene promoter: (-1793 C/G, -1234 T/C, -1185 G/A and -1051 A/G). All four polymorphisms are in strong linkage disequilibrium and recent reports have indicated these polymorphisms are associated with plasma vWF:Ag levels suggesting that one or more of these elements influence regulation of the vWF gene. We report that human endothelial cell-derived trans-acting factors display allelic preferences in binding activity to each polymorphic site. The common A allele variant of the -1051 polymorphism and the rarer A allele variant of the -1185 polymorphism provided specific binding of nuclear proteins. The G allele counterpart of these two variants did not produce any complex formation indicating that the nucleotide substitution at these positions alters the DNA binding ability of nuclear factors. The two alleles of the -1234 polymorphism produced two complexes with a similar migration pattern however stronger binding was found to the common T variant of this allele. Two specific complexes associated with the rarer G allele of the -1793 polymorphism, but only one associated with the C allele. Supershift experiments revealed that the trans-acting factor YYI recognised the slower migrating complex formed on the -1234 T/C and the -1051 A polymorphic sites with a strong binding preference for the -1234 T allele variant. The identification of YY1 as a component of the factors that recognise these elements suggests that this ubiquitous nuclear protein may play a role in the regulation of the vWF promoter.

Base Sequence↗

PubMed2001

Polymorphism of PCR-based markers targeting exons, introns, promoter regions, and SSRs in maize and introns and repeat sequences in oat.

Sequence databases could be efficiently exploited for development of DNA markers if it were known which gene regions reveal the most polymorphism when amplified by PCR. We developed PCR primer pairs that target specific regions of previously sequenced genes from Avena and Zea species. Primers were targeted to amplify 40 introns, 24 exons, and 23 promoter regions within 54 maize genes. We surveyed 48 maize inbred lines (previously assayed for simple-sequence repeat (SSR) polymorphism) for amplification-product polymorphism. We also developed primers to target 14 SSRs and 12 introns within 18 Avena genes, and surveyed 22 hexaploid oat cultivars and 2 diploid Avena species for amplification-product polymorphism. In maize, 67% of promoter markers, 58% of intron markers, and 13% of exon markers exhibited amplification-product polymorphisms. Among polymorphic primer pairs in maize, genotype diversity was highest for SSR markers (0.60) followed by intron markers (0.46), exon markers (0.42), and promoter markers (0.28). Among all Avena genotypes, 64% of SSR markers and 58% of intron markers revealed polymorphisms, but among the cultivars only, 21% of SSR markers and 50% of intron markers were polymorphic. Polymorphic-sequence-tagged sites for plant-breeding applications can be created easily by targeting noncoding gene regions.

Avena↗

PubMed2002

[Genetic polymorphisms of the renin-angiotensin system and essential hypertension].

BACKGROUND: The renin-angiotensin system (RAS) is known to regulate the blood pressure (BP). Several RAS polymorphisms have been associated with essential hypertension (EH), but there is uncertainty about this association. We examined whether the insertion/deletion (I/D) polymorphism of the angiotensin converting enzyme (ACE) gene, and the M235T polymorphism of the angiotensinogen (AGT) gene were associated with EH in a sample of Spanish hipertensive patients. PATIENTS AND METHOD: We studied 1,204 patients with EH (BP > 140/90 mmHg): 668 males, aged 50.8 (13.6) years with systolic BP 151.7 (19.1) and diastolic BP 94.3 (13) mmHg [mean (SD)] and 536 females, aged 52.4 (13.9) years with systolic BP 155.1 (19.8) and diastolic BP 94.5 (12.3) mmHg. As a control group, 367 men and 280 women with no family history of cardiovascular disease who had a normal blood pressure were included. Polymorphisms were determined by PCR amplification of genomic DNA, followed by enzyme digestion for the AGT gene polymorphism. RESULTS: The genotype distribution and allele frequencies of the two RAS polymorphisms were similar in hypertensive and control subjects. Similarly, there were no differences in BP level with regard to the genotype in male or female patients. In addition, we did not find any compound effect of the I/D ACE gene and M235T AGT gene polymorphisms on BP levels in hypertensive subjects. CONCLUSIONS: This study suggests that in the population studied, the contribution of the ACE I/D polymorphism and the AGT M235T polymorphism in the development of EH is less important than previously estimated.

Female↗

PubMedDate not supplied

Polymorphisms of the interleukin-1 gene cluster and ovarian cancer.

OBJECTIVE: Interleukin-1 (IL-1) is known to be critically involved in ovarian carcinogenesis. We investigated a panel of polymorphisms of the IL-1 and the IL-1 receptor antagonist (IL-1 RA) genes in patients with ovarian cancer. METHODS: One hundred thirty-four patients with surgically staged ovarian cancer, 27 patients with borderline ovarian cancer, and 134 healthy controls were genotyped for three polymorphisms of the IL-1 gene (-889 C/T polymorphism of the IL-1alpha gene [IL1A], -511 C/T polymorphism of the IL-1beta promoter [IL1B promoter], a polymorphism of IL-1beta exon 5 [IL1B exon 5]), and an 86-base pair repeat in intron 2 of the IL-1 RA gene [IL1RN]) using polymerase chain reaction and pyrosequencing. RESULTS: Allelic frequencies did not differ between patients with ovarian cancer and controls. In the ovarian cancer group, polymorphism did not correlate with any of the investigated clinicopathologic variables, including tumor stage, lymph node, and histologic grade. In univariate and multivariate models, there was no correlation between any polymorphism and patients' overall and disease-free survival. CONCLUSION: We investigated interleukin polymorphisms in ovarian cancer but did not find any association between common polymorphisms of IL1A, IL1B, and IL1RN and the occurrence of ovarian cancer. Allelic variation within the IL-1 gene clusters does not seem to play a role in ovarian carcinogenesis and does not appear to be a useful tool for possible screening and risk evaluation.

Alleles↗

PubMed2003

Nitric oxide synthase 2 promoter polymorphisms and systemic lupus erythematosus in african-americans.

OBJECTIVE: Systemic lupus erythematosus (SLE) is an autoimmune disease in which morbidity and mortality are higher in African-Americans. The etiology of this racial disparity is unknown. A genetic predisposition to enhanced nitric oxide (NO) production may predispose African-Americans to develop SLE and may increase disease severity. We have demonstrated a correlation between NO production and disease activity in SLE. Two polymorphisms in the inducible NO synthase (NOS2) promoter region (G-954C and CCTTT microsatellite repeat polymorphisms) are associated with improved outcome in some African patients with malaria. This study was designed to determine if these polymorphisms are associated with SLE. METHODS: We assessed the frequency of both the G-954C and CCTTT microsatellite repeat NOS2 promoter polymorphisms in a cohort of patients with SLE and age, sex, and race matched controls in North Carolina and South Carolina. RESULTS: Both polymorphisms were more frequent among African-American female SLE patients when compared with controls (p = 0.04 for the G-954C polymorphism and p = 0.03 for the CCTTT-8 repeat polymorphism). Further, the G-954C and CCTTT-8 repeat polymorphisms were in linkage disequilibrium (D cent = 0.89, p = 0.0001) among African-American female SLE patients. CONCLUSION: Altered genetic control of NOS2 transcription may be a risk factor for SLE among African-American females. The extent of linkage disequilibrium between the G-954C and CCTTT-8 repeat NOS2 promoter polymorphisms suggests that they were co-inherited.

Alleles↗

PubMed2003

[Analysis on association of glucocorticoid receptor gene polymorphism with steroid-resistance in idiopathic nephrotic syndrome of children].

OBJECTIVE: The nephrotic syndrome is defined by heavy proteinuria, edema, hypoalbuminemia, and hyperlipidemia. Idiopathic nephrotic syndrome (INS) mainly occurs in children, which is generally treated with glucocorticoids. The majority of patients are steroid-sensitive (SSINS) while steroid-resistance occurs in a subset of NS children (SRINS). Although intensive efforts have been undertaken to study the associations between SRINS and renal pathological changes, pharmacokinetics, and the GR density and binding affinity, the mechanisms underlying steroid-resistance are still not elucidated entirely. The authors hypothesized that it might be associated with polymorphisms in the glucocorticoid receptor gene (NR3C1). The study aimed to screen the NR3C1 gene for polymorphisms in genomic DNA samples from SRINS, SSINS children and control group, and to analyze the association of the polymorphisms in the NR3C1 gene and SRINS of children. METHODS: Totally 39 SRINS and 67 SSINS children (81 males and 25 females with the mean age of 7 years) were involved in the study. Umbilical cord blood of 62 normal neonates and peripheral blood of 2 healthy volunteers were selected as controls. Genomic DNA was isolated from peripheral blood lymphocytes of all subjects. All the NR3C1-coding exons and intron-flanking portions were amplified by polymerase chain reaction (PCR). For polymorphism screen, PCR products were analyzed by denaturing high performance liquid chromatography (DHPLC). DNA fragments with aberrant elution profiles were re-amplified and sequenced directly. RESULTS: Twelve aberrant elution profiles were identified with DHPLC in SRINS, SSINS and controls. Among them, 6 previously reported polymorphisms and 6 novel polymorphisms were confirmed by sequencing (198G > A, 200G > A, IVSD-16G > T, 1896C > T, 2166C > T, 2430T > C; novel, 1206C > T, 1374A > G, IVSG-68_IVSG-63delAAAAAA, 2193T > G, IVSH-9C > G, 2382C > T), and 3 groups of SNPs were in complete linkage disequilibrium, which resulted in 3 different haplotypes ([198G > A + 200G > A], [1374A > G + IVSG-68_IVSG-63delAAAAAA + IVSH-9C > G + 2382C > T], [1896C > T + 2166C > T + 2430T > C]). The last two genotypes were first reported. The genotype frequencies of the 2 novel haplotypes were 10.3% vs 1.5% in SRINS and SSINS, and 15.4% vs 7.5% in SRINS and SSINS, respectively. Other polymorphisms were relatively rare detectable both in patients and controls. CONCLUSION: Twelve polymorphisms in the NR3C1 gene were detected with the technique of DHPLC, of which six polymorphisms were identified at the first time. Two types of newly found haplotypes were associated with steroid-resistant idiopathic nephrotic syndrome of children, which might be responsible for steroid-resistance in partial idiopathic nephrotic syndrome of children.

Adolescent↗

PubMed2004

[Gene polymorphisms of rennin-angiotensin system and coronary artery thrombosis disease].

To investigate the distribution frequencies of angiotensin-converting enzyme (ACE), angiotensinogen (AGT), angiotensin II I type receptor (AT1R) genotypes in Chinese, to find the relationships between polymorphisms of ACE, AGT and AT1R gene, and coronary artery thrombosis disease (CATD) and to study the interactions of themselves, PCR and PCR-RFLP techniques were performed to determine the genotypes of ACE, AGT and AT1R gene in CATD group (192 cases) and control group (110 cases). The results showed that (1) genotype frequencies of the three polymorphisms in the control group were 12.2% (DD), 43.9% (ID), and 43.9% (II) for the ACE I/D polymorphism; 8.2% (MM), 36.7% (MT), and 55.1% (TT) for AGT M235T polymorphism; 91.8% (AA), 8.2% (AC) for AT1R A1166C polymorphism respectively; (2) there were no significant differences between patients in either the control group, the non-MI group, or the MI group in any genotype frequency of all these three genes (P >0.05). (3) the odds ratio for CATD in subjects carrying both AT1R-AC and AGT-TT genotype was 3.517 (95% CI 0.988 - 12.527), compared with those carrying AT1R-AA and AGT-TT genotype and was 15.000 (95% CI 1.940-115.963), compared with those carrying AT1R-AC and AGT-MM/MT genotype. In subjects with AT1R-AC genotype, there was also a great difference of ACE D allele frequency between control group and CATD group (P=0.017). It is concluded that genotype frequencies of ACE I/D polymorphism, AGT M235T polymorphism, and AT1R A1166C polymorphism were obviously different from those in western countries. Although these three polymorphisms were not independent risk factors for CATD or myocardial infarction (MI) in Chinese, AT1R-AC genotype has a significant synergistic effect with AGT-TT genotype. There is also a obvious interaction between AT1R-AC genotype and ACE D allele.

Angiotensinogen↗

PubMedDate not supplied

Genetic polymorphism of interleukin-8 (IL-8) is associated with Helicobacter pylori-induced duodenal ulcer.

BACKGROUND AND AIMS: Helicobacter pylori infection almost invariably causes chronic gastritis, but only a proportion of the infected subjects develop peptic ulcers. The local inflammation associated with H. pylori infection is characterized by an increased production of the proinflammatory cytokines IL-1-B, IL-6, IL-8 and TNF-alpha. Since such cytokine production is often determined by the genetic polymorphism of regions regulating cytokine gene expression, we investigated the relationship between TNF-alpha and IL-8 polymorphisms and the development of duodenal ulcer disease. We also sought a correlation between the promoter polymorphism of the lipopolysaccharide (LPS) receptor CD14 and the formation of peptic ulcer, because CD14 plays a crucial role in the initiation of the cytokine cascade. METHODS: Genomic DNA extracted from the peripheral blood of 69 patients with H. pylori-positive duodenal ulcer disease and 47 H. pylori-positive healthy controls was analyzed for TNF-alpha -308 promoter polymorphism by RFLP, and for IL-8 -251 polymorphism by ARMS. Genetic polymorphism within the promoter of the CD14 gene was identified using the LightCycler instrument via melting point analysis. RESULTS: No significant correlation could be revealed between the TNF-alpha and CD14 promoter polymorphisms and the clinical outcome of H. pylori infection. The IL-8 A/T heterozygote mutant variant was detected with a significantly higher frequency (65.22%) among the ulcer patients than among the healthy, H. pylori-positive blood donors (36.17%), while the frequency of the normal allelic genotype (TT) was significantly higher in the control group (44.6% vs 15.9%). CONCLUSION: Analysis of the genetic predisposition to enhanced cytokine production revealed a significant association only for the IL-8 polymorphism. This observation draws attention to the possible importance of IL-8 polymorphism as a genetic predisposing factor in the pathomechanism of H. pylori-induced duodenal ulcer disease, and to the relative protection from duodenal ulcer disease that is associated with the TT genotype.

Adult↗

PubMed2005

[Study of relations between matrix metalloproteinase-9 polymorphism (C-1562T) and acute coronary syndrome in Han population of China].

OBJECTIVE: To investigate the association between acute coronary syndrome (ACS) and functional matrix metalloproteinase-9 polymorphism (C-1562-T). METHODS: This study was conducted with a case-control design including 101 patients with angiographically documented ACS and 105 control subjects who were free from coronary artery disease and had normal angiograms. Genotype was determined by polymerase chain reaction-restriction fragment length polymorphism for the common C-1562-T functional promoter polymorphism of the MMP-9 gene.The relationship between the polymorphism in the MMP-9 gene and the severity of coronary arterial stenosis was analyzed. RESULTS: The results of individual polymorphisms analysis showed that the frequency of C/T and T/T genotypes of the C-1562-T polymorphism (27.2%) in patients with ACS was significantly higher than that in those with a normal angiogram (13.34%).The frequencies of -1562T allele were 14.9% and 7.2% in ACS group and control group respectively (Chi2 = 5.617, P = 0.018). The frequencies of C/T and T/T genotypes of the C-1562-T polymorphism were not statistically different among ACS patients with normal and one,two,three or more significantly diseased vessels (Chi2 = 0.601, P = 0.896). CONCLUSION: The present findings suggest that the genetic polymorphism in MMP-9 promoter (C-1562-T) is associated with the susceptibility to ACS in the Han population of China. And the C-1562-T polymorphism may not be useful as a predictor of the severity of coronary atherosclerosis.

Acute Coronary Syndrome↗

PubMed2006

Interleukin-10 promoter polymorphisms in patients with hepatitis B virus infection or hepatocellular carcinoma in Chinese Han ethnic population.

BACKGROUND: Since single nucleotide polymorphisms (SNPs) can serve as gene markers, polymorphism profiles may help scientists to identify the full collection of genes that contribute to the development of complex diseases such as cancer. The distribution of interleukin-10 (IL-10) promoter polymorphisms in Chinese Han ethnic patients with hepatitis B virus (HBV) infection and hepatocellular carcinoma (HCC) was investigated in this study. METHODS: The polymorphisms of IL-10 promoter region were detected by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and sequencing. Sixty-six health controls, 42 patients with HBV infection, 30 HCC patients, and cell line SMMC-7721 were examined this way. RESULTS: Polymorphisms of T/C or T/N on -872 site occurred frequently in Han ethnic population. Polymorphisms were detected in HBV and HCC patients and cell line SMMC-7721. The hotspot among the polymorphisms was inserting base A between -1058 and -1057. CONCLUSION: Polymorphisms of IL-10 promoter in HBV and HCC patients may be associated with HBV infection and HCC development.

Asian People↗

PubMed2006

Association of VEGF and eNOS gene polymorphisms in type 2 diabetic retinopathy.

PURPOSE: Vascular endothelial growth factor (VEGF) is a major mediator of angiogenesis, and nitric oxide (NO) is an upstream and downstream regulator of VEGF mediated angiogenesis. VEGF and NO have been suggested to play an important role in the pathogenesis of microvascular complications in diabetic retinopathy (DR). The objective of this study was to examine the genetic variations of the VEGF and eNOS gene and assess their possible relationship to DR in type 2 diabetic patients in the Indian population. METHODS: In this study, 210 unrelated patients were enrolled and categorized into two study groups: a DR group, consisting of patients with proliferative diabetic retinopathy, and a diabetic without retinopathy (DWR) group comprised of patients with type 2 diabetes of more than 15 years duration who showed no signs of DR or had fewer than five dots or blot hemorrhages. Association of the genetic polymorphisms in the promoter and 5' UTR region of VEGF and the intron4 region of eNOS were studied. Total genomic DNA was isolated from peripheral blood leukocytes. PCR-RFLP analysis was performed for all samples to evaluate the genotypes. The distributions of the genotypes were compared using the chi2 test. Haplotype estimation and multiple logistic regression analysis were carried out to analyze the significance of polymorphisms. RESULTS: We investigated four reported polymorphisms in the VEGF (5' UTR, promoter) and one reported polymorphism (intron 4) in the eNOS gene in Type 2 diabetes patients with (n=120) and without (n=90) retinopathy. The genotype distribution of the C(-7)T, T(-1498)C, and C(-634)G polymorphisms of VEGF differed significantly between patients with DR and DWR (p=0.001, p=0.0001, and p=0.021, respectively). Allele C in the -1498 region (p=0.0001) and T in -7 region (p=0.002) were also found to be significantly increased in patients with retinopathy. Calculated odds ratios (OR) for three heterozygous genotypes of C(-7)T, T(-1498)C, and C(-634)G regions were 4.17 (95% CI: 1.90-9.18, p=0.0001), 4.37 (95% CI: 2.44-7.84, p=0.0001), and 2.33 (95% CI: 1.24-4.36, p=0.008), respectively, and was found to be significantly higher in the DR group when compared with the DWR group. Multiple logistic regression analysis revealed that the nongenetic parameters, age (p=0.024) and duration of diabetes (p=0.009), and the genetic parameters, like VEGF C(-7)T (p=0.002) and T(-1498)C (p=0.001) polymorphisms, were significantly associated with DR. The frequencies of haplotype consisting of the majority of alleles in VEGF were found to be significantly associated with DR. The genotype distribution of eNOS did not differ significantly between the two study groups, and therefore the eNOS intron 4 polymorphism was considered to be less significant. CONCLUSIONS: This is the first study to report VEGF and eNOS gene polymorphisms in patients with DR in the Indian population. The data suggest that the polymorphisms in the 5' UTR and promoter region of VEGF could be regarded as a major genetic risk factor for DR.

5' Untranslated Regions↗

PubMed2006

Correlation between methotrexate efficacy & toxicity with C677T polymorphism of the methylenetetrahydrofolate gene in rheumatoid arthritis patients on folate supplementation.

BACKGROUND & OBJECTIVES: C677T polymorphism in the methylenetetrahydrofolate reductase (MTHFR) gene has been proposed as a pharmacogenomic marker for toxicity of methotrexate (MTX). We studied the relationship between the C677T gene polymorphism and toxicity and efficacy of MTX in patients with rheumatoid arthritis (RA) on folate supplementation. METHODS: A total of 150 RA patients fulfilling American College of Rheumatology (ACR) criteria and on MTX treatment were evaluated. The mean age of the patients was 42.9 +/- 11.1 yr, mean disease duration was 7.65 +/- 5.2 yr and the mean duration of MTX treatment was 26.1 +/- 20.6 months. Genotype analysis of MTHFR gene was done by PCR and restriction enzyme method. Primary endpoint for treatment efficacy was change in disease activity score 28 (DAS28) from baseline. Drug toxicity was evaluated by blood count, renal and liver function tests and a standardized questionnaire. RESULTS: The mean DAS at baseline was 5.02 +/- 0.8. All patients received 10 mg/wk folic acid supplementation. Forty two per cent (63/150) of the patients had C677T polymorphism of which 4 were homozygous (T/T) and 59 were heterozygous (C/T). The baseline characteristics of the patients with or without polymorphism were comparable. The frequency of adverse events was not increased in patients with C677T polymorphism with 11 patients experiencing adverse events as compared to 19 in the group without polymorphism (of whom 4 and 7 patients respectively discontinued treatment). The C677T polymorphism was not associated with any difference in response to treatment. INTERPRETATION & CONCLUSION: Our findings suggest that C677T polymorphism in the MTHFR gene is not predictive of toxicity or efficacy of MTX treatment in RA patients receiving folate supplementation. Further studies need to be done to look at polymorphisms in other enzymes that may have association with MTX clinical efficacy and toxicity.

Adult↗

PubMed1989

Polymorphisms of the immunoglobulin heavy-chain delta gene and association with other constant-region genes.

Polymorphisms have previously been reported for the C mu, C alpha, C epsilon, and C gamma genes of the immunoglobulin heavy-chain (IGH) gene cluster. Here we report polymorphisms of the IGH C delta gene region, observed using the enzymes ApaI, AvaII, TaqI, and XbaI. The TaqI and XbaI polymorphisms were used in an investigation of linkage disequilibrium throughout the cluster of constant-region genes. The TaqI polymorphism, located 5' to the C delta gene, is in linkage disequilibrium with a polymorphism of the C mu switch region. The XbaI polymorphism, which is in the vicinity of the C delta 2 exon, is not strongly associated with any other polymorphisms, including the TaqI polymorphism and the Gm polymorphism of C gamma 3. Although there is a high degree of association between most genes of the IGH region, there is a lack of association between C delta and C gamma 3, which may indicate a hot spot for recombination.

DNA↗