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PubMedDate not supplied

Angiotensin-converting enzyme (ACE) gene polymorphism in type II diabetic patients with increased albumin excretion rate.

Approximately one in three patients with diabetes is at risk of developing kidney disease, despite current methods of treatment. It has long been suspected that diabetic kidney disease has a genetic basis, but this has been difficult to prove. Polymorphisms of the angiotensin-converting enzyme (ACE) gene have been shown to be related to the occurrence of nephropathy in type I diabetic patients. This study showed that there was no association in the ACE genotype frequency and increased albumin excretion rate in type II diabetic patients.

Adult↗
PubMed2005

Blood oxidative stress markers in Gaucher disease patients.

BACKGROUND: Gaucher disease (GD) is the most common glycosphingolipidosis resulting in accumulation of glucoceramide. The most effective treatment for this disease is enzyme replacement therapy (ERT) which involves recombinant enzyme infusion. Enzymatic deficiency in GD patients may induce a cascade of events culminating in secondary effects such as the production of reactive oxygen species (ROS). We investigated the relationship between ROS and GD by analyzing blood oxidative stress markers in GD patients submitted to ERT at different stages during the treatment. METHODS: Blood were collected before and just after enzyme infusion. Red blood cell catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD) and total glutathione (tGSH), and plasma thiobarbituric acid reactive substances (TBARS) were assayed by spectrophotometry. Homocysteine concentrations and related polymorphisms were also studied. Control individuals matched for sex and age were also analyzed. RESULTS: Concentrations of homocysteine and TBARS, and GPx enzyme activity were not different in ERT-treated GD patients. CAT activity was higher while SOD was lower in patients compared to controls. No variations in any of these parameters were found before and just after ERT. Regarding tGSH, a significant increase was observed in GD patients after infusion. Genotypic frequencies studied did not differ from controls or other Brazilian samples. CONCLUSION: ERT-treated GD patients show an improvement in antioxidant capacity, which is further increased just after recombinant enzyme infusion.

Adolescent↗
PubMed2006

Association of cryptorchidism with Gly146Ala polymorphism in the gene for steroidogenic factor-1.

Genotyping analysis was performed for Gly146Ala polymorphism in the gene for steroidogenic factor-1 (SF-1), which is known to reduce the transactivation function by approximately 20%, in 72 cryptorchid patients and 136 control males, revealing that the Ala allele, the Ala/Gly genotype, and the Ala/Ala plus Ala/Gly genotype frequencies were significantly higher in the patients than in the control males. The results suggest that the Gly146Ala polymorphism may be a susceptibility factor for the development of cryptorchidism (CO).

Adolescent↗
PubMed2006

Rapid genotyping of lipopolysaccharide-binding protein (LBP) C(1341)-->T (Leu(436)-->Phe) polymorphism by LightCycler real-time PCR.

Lipopolysaccharide (LPS) is an exdotoxin found in the outer membrane of gram-negative bacteria. In circulation, LPS is bound by LPS-binding protein (LBP), which participates in cell activation by transferring LPS to CD14 and Toll-like receptor 4. A high LPS concentration may give rise to an exaggerated immune response, which may lead to septic shock during septicemia. However, LBP also neutralizes and removes LPS by transferring it to plasma lipoproteins. Recently, the presence of an amino acid-changing polymorphism in the LBP gene was reported, which, in men, was associated with sepsis and its severity and with myocardial infarction. Here, we describe a new LightCycler real-time PCR method for genotyping this LBP C(1341)-->T (Leu(436)-->Phe) polymorphism. In our study population of 393 Finnish blood donors, the genotype frequencies were: 86% TT, 13% CT and 1% CC.

Acute-Phase Proteins↗
PubMed2005

Sex-specific effect of APOAV variant (Val153>Met) on plasma levels of high-density lipoprotein cholesterol.

The importance of the APOAV gene for the determination of plasma triglyceride levels has been suggested by creations of transgenic and knockout mice and confirmed in population studies. We examined whether the newly detected APOAV variant is associated with plasma lipid levels and risk of myocardial infarction (MI). APOAV polymorphism (Val153>Met) was genotyped in 1191 males and 1368 females representatively selected from the Czech population. Lipid levels were analyzed in 1997 and 2001 in all individuals. Subsequently, we have analyzed the genotype frequencies of APOAV polymorphism in 435 male patients with MI. Val153>Met variation in the APOAV gene affects the plasma high-density lipoprotein cholesterol levels showing a higher level in Val/Val homozygotes than in Met carriers in both years (1.51 +/- 0.36 and 1.52 +/- 0.37 mmol/L compared with 1.42 +/- 0.33 and 1.39 +/- 0.35 mmol/L, P < .01). This association has been observed in females but not in males. Other analyzed lipid parameters (total cholesterol, low-density lipoprotein cholesterol, and triglycerides) have not been associated with APOAV Val153>Met variant. In a group of patients with MI, the frequency of the Met153 carriers was not significantly different from the male population sample (6.5% vs 6.4%). Val153>Met variation in the APOAV gene plays a sex-specific role in genetic determination of plasma high-density lipoprotein cholesterol levels, but does not influence risk of MI in males.

Adult↗
PubMed2006

Relationship between polymorphisms 804C/A and 252A/G of lymphotoxin-alpha gene and -308G/A of tumor necrosis factor alpha gene and diabetic retinopathy in Japanese patients with type 2 diabetes mellitus.

To clarify whether polymorphisms of the lymphotoxin-alpha (LTA) gene and tumor necrosis factor alpha (TNF-alpha) gene were related to diabetic retinopathy (DR), we performed a case-control study in 251 Japanese patients with type 2 diabetes mellitus participating in a multicenter research protocol. Genetic analyses were performed by using a fluorescent allele-specific DNA primer assay system. Diabetic retinopathy was diagnosed in a masked manner by an independent ophthalmologist using fundus photographs and was classified as nondiabetic retinopathy (NDR), nonproliferative retinopathy (NPDR), and proliferative retinopathy (PDR). The results showed that the genotype frequencies of 804C/A in exon 3 and 252A/G in intron 1 of the LTA gene were not significantly different among patients with NDR, NPDR, and PDR. A allelic frequency of the TNF-alpha gene (-302A/G in promoter) was also identical among NDR, NPDR, and PDR groups. Multivariate logistic regression analyses showed that significant associations with DR were glycosylated hemoglobin level and diabetes duration, but not polymorphisms of the LTA gene or TNF-alpha gene. In conclusion, the present study showed no association between polymorphisms 804C/A and 252A/G of the LTA gene and -302A/G of the TNF-alpha gene and DR in Japanese type 2 diabetic patients.

Aged↗
PubMed2004

No genetic association between polymorphisms in the AMPA receptor subunit GluR4 gene (GRIA4) and schizophrenia in the Chinese population.

The glutamatergic dysfunction hypothesis of schizophrenia suggests genes involved in glutamatergic transmission as candidates for schizophrenia-susceptibility genes. It has recently been reported that some haplotypes in the AMPA receptor subunit GluR4 Gene (GRIA4), which is located on chromosome 11q22, are positively associated with schizophrenia in the Japanese population. In order to assess the role of GRIA4 in schizophrenia, we examined three reported positive SNPs (single nucleotide polymorphisms): rs609239, rs641574 and rs659840 at the GRIA4 locus in schizophrenic cases (n = 372) and controls (n = 392) of the Chinese population. Although we had observed similar allele and genotype frequencies compared with that in the Japanese population, no evidence was found for association with the disease in the analysis of either single nucleotide polymorphisms (all P-values > 0.300) or haplotype relative risk (all P-values > 0.088). Our results suggest that the three SNPs of GRIA4 are unlikely to play a major role in the susceptibility to schizophrenia in the Chinese population.

Adult↗
PubMed2006

Association study of sporadic Parkinson's disease genetic risk factors in patients from Russia by APEX technology.

Most patients with Parkinson's disease (PD) have sporadic form of the disease with a multifactorial etiology due to interactions between environmental conditions and the genetic constitution of the individuals. We have analyzed by APEX technology 50 single nucleotide polymorphisms (SNPs) in 19 genes related to cholecystokinin, serotonin, dopamine and opioid neurotransmission. Significant differences in the allele and genotype frequencies between the controls and PD patients were detected for four SNPs from three genes (serotonin 2A receptor (rs6311, P=0.043), Wolfram syndrome 1 (rs1801211, P=0.007), proopiomelanocortin (rs28930368, P=0.026 and rs2071345, P=0.027) genes). Two SNPs in proopiomelanocortin (POMC) gene were also associated with different clinical forms of PD. Our data suggest that at least three genes involved in neurotransmitter systems may have more specific role in genetic predisposition to PD.

Aged↗
PubMed2001

Two polymorphisms in the apo A-IV gene and familial combined hyperlipidemia.

Linkage and association of the apo AI-CIII-IV gene region to familial combined hyperlipidemia (FCHL) was reported previously, based on the presence of genetic variants in the apo CIII and apo AI gene. No data were available yet on the contribution of the apo A-IV locus. Two DNA variants in exon 3 of the apo A-IV gene, A (Thr)(347)T (Ser) and [CTGT](3-4) were characterized by sequencing the coding region of the apo A-IV gene and were analyzed in our Dutch FCHL cohort (30 probands, 159 affected relative, 317 unaffected relatives and 218 spouses). The genotype frequency of the A(347)T variant was different in probands and spouses. In probands no 2/2 carriers were found, resulting in a significant decreased frequency of the 2-allele (P<0.05). This was suggestive for a protective role of the presence of the serine (T) allele on the prevalence of FCHL. No difference in frequency distribution was found for the [CTGT](3-4) variant between the groups. Homozygous 4/4 carriers in spouses had a more favorable lipid profile (LDL-cholesterol and apo B, P<0.05). The absence of linkage disequilibrium of the A(347)T with other markers in the gene cluster, and the absence of linkage disequilibrium with [CTGT](3-4) marker and the MspI-AI marker in the apo A-I promoter showed that these two apo A-IV variants reside on different haplotypes from the apo A-I and apo C-III markers. This was illustrated by extensive haplotype analysis. The present data on the contribution of DNA variants in the apo A-IV gene support our previous observations that the apo AI-CIII-AIV gene cluster has a complex genetic contribution to FCHL both by conferring susceptibility and protection.

Adult↗
PubMed2003

HLA haplotypes and TNF polymorphism do not associate with longevity in the Irish.

Polymorphism of the human leukocyte antigen has been implicated in a number of autoimmune disorders including ageing. In the course of the present study, no association of the human leukocyte antigen (HLA)-A1, B8, DR3 haplotype with a male Irish aged population, as previously reported, was observed. Two polymorphic nucleotides in the TNF cluster (G-308A TNF-alpha and G+252A TNF-beta), associated with increased TNF-alpha production, were shown to be in tight linkage disequilibrium with the class I and II HLA loci, generating HLA haplotypes with extended linkage disequilibrium. However, no age-related allele or genotype frequencies were observed for either polymorphic nucleotide.

Adult↗
PubMed1998

Absence of association between Alzheimer disease and the -491 regulatory region polymorphism of APOE.

A novel polymorphism (-491 A/T) within the regulatory region on the apolipoprotein E gene has recently been reported to be associated with risk for Alzheimer disease (AD). To test this association in an independent data set, we have examined this polymorphism in a sample of 88 well-characterized AD cases and compared the allele frequency and genotype frequencies for this polymorphism with those observed in 112 cognitively normal subjects drawn from the same ethnic group. These results suggest that in the current data set at least, the -491 A/T polymorphism is not associated with risk for AD, but may be in partial linkage disequilibrium with the APOE epsilon2/epsilon3/epsilon4 polymorphism.

Aged↗
PubMed2003

Serotonin transporter gene polymorphisms and platelet [3H] paroxetine binding in premenstrual dysphoria.

The purpose of this study was to investigate if women with premenstrual dysphoria differ from controls with respect to the number of platelet serotonin transporters, and with respect to three polymorphisms in the gene coding for the serotonin transporter: a 44 base pair insertion/deletion in the promoter region, a variable number of tandem repeats in the second intron, and a single nucleotide polymorphism in the 3' untranslated region. Also, the possible relationship between the three polymorphisms and platelet serotonin transporter density was analyzed. The density of platelet [(3)H]paroxetine binding sites was significantly lower in women with premenstrual dysphoria than in controls, but patients and controls did not differ with respect to allele or genotype frequency for any of the three polymorphisms examined. A significant association between the number of platelet serotonin transporters and the promoter polymorphism was observed, subjects being homozygous for the short (deletion) variant having higher platelet serotonin transporter density than subjects carrying the long (insertion) allele. The results support the assumption that serotonin-related psychiatric disorders-such as premenstrual dysphoria-may be associated with a reduction in platelet [(3)H]paroxetine binding, but argue against the notion that this reduction is due to certain variants of the serotonin transporter gene being more common in patients than in controls.

Adolescent↗
PubMed2000

Swiss Caucasian population data for the STR loci D2S1338 and D19S433 using the AmpFISTR SGM plus PCR amplification kit.

Allele and genotype frequencies for the ten STR loci D3S1358, VWA, D16S539, D2S1338, D8S1179, D21S11, D18S51, D19S433, TH01, FGA were determined in a Swiss Caucasian population sample (n=206) using the AmpFISTR SGM Plus Amplification kit. Electrophoresis was carried out on an ABI PRISM CE 310 Genetic Analyzer instrument. Previously, allele frequencies were published for the 13 STR loci D3S1358, VWA, FGA, D8S1179, D21S11, D18S51, D5S818, D13S317, D7S820, THO1, TPOX, CSF1PO and D16S539 for the same samples (n=206) amplified with the AmpFISTR Profiler Plus and Cofiler PCR Amplification kits. Since the results for the eight loci D3S1358, VWA, FGA, D8S1179, D21S11, D18S51, THO1, D16S539 shared between the AmpFISTR SGM Plus, Profiler Plus and Cofiler PCR Amplification kits already are published, only the allele frequencies for the two STR loci D2S1338 and D19S433 are reported in this paper. The two loci meet Hardy-Weinberg expectations. In addition, there is little evidence for association of alleles among the 15 loci (amplified with the Profiler, Cofiler, and SGM Plus amplification kits). The allelic frequency data can be used in forensic analyses to estimate the frequency of a multiple STR locus DNA profile in the Swiss population.

Alleles↗
PubMed2001

The Trp64Arg polymorphism of the beta3-adrenergic receptor gene is not associated with training-induced changes in body composition: The HERITAGE Family Study.

OBJECTIVE: To investigate the association between the Trp64Arg polymorphism of the beta3-adrenergic receptor gene and changes in body composition in response to endurance training. RESEARCH METHODS AND PROCEDURES: Adult sedentary white and black subjects participating in the HERITAGE Family Study were measured before and after 20 weeks on endurance training for the body mass index, fat mass, percentage of body fat, fat-free mass, sum of eight skinfolds, and subcutaneous, visceral, and total abdominal fat areas. The association between the Trp64Arg polymorphism and the response phenotypes, computed as the difference between pre- and post-training values, was tested by analysis of covariance separately in men and women. The gene by race interaction term was also tested. RESULTS: No race differences were observed for allelic and genotype frequencies. Training resulted in significant reduction of body fat in both men and women. No association of the Trp64Arg polymorphism was observed with training-induced changes for any of the body composition phenotypes in both men and women. DISCUSSION: These results suggest that the Trp64Arg polymorphism of the beta3-adrenergic receptor gene is not related to changes in body composition in response to exercise training.

Adipose Tissue↗
PubMed1998

Absence of association between a common mutation in the methylenetetrahydrofolate reductase gene and the risk of coronary artery disease.

BACKGROUND: Elevated total plasma homocysteine levels are associated with an increased risk of coronary artery disease. Plasma homocysteine levels are influenced by nutritional and hereditary factors. A point mutation (cytosin to thymidine substitution; C677-->T) in the gene encoding methylenetetrahydrofolate reductase (MTHFR), has been reported to render the enzyme thermolabile and has been associated with elevations in homocysteine levels in homozygous carriers (TT genotype). METHODS: To examine the hypothesis that the T allele (coding for the thermolabile defect of MTHFR) influences the risk of coronary artery disease, we genotyped 340 patients with coronary artery disease and 105 control subjects in whom coronary artery disease was excluded by coronary angiography. Furthermore, we studied the genotype frequency in 104 age- and sex-matched healthy persons as a control group without signs of atherosclerotic disease. RESULTS: Allele frequencies for C (wild-type allele) and T allele (mutant allele) were 0.68 and 0.32 respectively in the healthy control subjects, 0.66 and 0.34 respectively in patients with angiographically excluded coronary artery disease and 0.69 and 0.31 respectively in coronary artery disease patients (P = NS). The allele frequencies of the total study population were 0.68 and 0.32. CONCLUSION: Our data show that homozygosity for the C677-->T mutation in this European population is not associated with increased risk of coronary artery disease. This finding suggests that the C677-->T mutation of the MTHFR gene does not represent a marker for increased cardiovascular risk.

Adult↗
PubMed2002

Polymorphisms of genes affecting thrombosis and risk of myocardial infarction.

BACKGROUND: As thrombosis is an essential factor in the pathogenesis of acute myocardial infarction (AMI), the genes of proteins affecting haemostasis are good candidate genes for AMI. DESIGN: Associations of the known polymorphisms of the coagulation factor VII (FVII) gene (R353Q), the coagulation factor XIII (FXIII) gene (V34L) and the glycoprotein Ia (Gp1a) gene (C807T) with the occurrence of AMI were studied in 142 AMI survivors and 142 age- and sex-matched control subjects. RESULTS: Among those who smoked, the L34 allele of the amino acid FXIII polymorphism was less common in the AMI patients (16%) than in the controls (27%) (P = 0.06), suggesting a possible interaction of AMI risk between the FXIII genotype and smoking status. No differences in the allele or genotype frequencies of the studied polymorphisms were seen between the whole study groups. Logistic regression analysis showed the carriers of the L34 allele of the FXIII amino acid polymorphism to have a significantly (P = 0.03) lower AMI risk compared with those homozygous for the V34 allele (odds ratio = 0.54, 95% confidence interval 0.31-0.93). CONCLUSION: The L34 allele of the amino acid polymorphism of the FXIII gene is associated with a decreased risk of AMI, and this protecting association seems to be more pronounced in smokers.

Blood Coagulation Factors↗
PubMed2002

The endothelial nitric oxide synthase (Glu298Asp and -786T>C) gene polymorphisms are associated with coronary in-stent restenosis.

AIMS: Coronary stent deployment is a major advance in percutaneous treatment of ischaemic heart disease, but 10-40% of patients still develop angiographic restenosis by 6 months due to neointimal hyperplasia. Patient-specific factors, including genetic factors, can contribute to this process. We have conducted a prospective study to examine the involvement of genetic risk factors (eNOS, ACE, MMP-3, IL-6, and PECAM-1) in restenosis following coronary stent deployment. METHODS AND RESULTS: A total of 226 patients who underwent elective and successful coronary artery stenting to de novo lesions in native coronary arteries were studied. Two hundred and five (90.7%) patients were restudied by coronary angiogram at 6 months and the stented lesions were assessed using an automated quantitative angiography system. Genotype was determined by polymerase chain reaction (PCR) and restriction enzyme digestion. Restenosis rate, defined as >or=50% diameter stenosis, was 29.3%. The overall genotype frequency distributions were in Hardy-Weinberg equilibrium for all variants. Carriers of the 298Asp allele of the eNOS Glu298Asp polymorphism showed a higher frequency of restenosis with an odds ratio of 1.88 (95%CI: 1.01-3.51, P=0.043) compared to 298Glu homozygotes. Carriers of the -786C allele of the eNOS -786T>C polymorphism also showed a higher frequency of restenosis with odds ratio of 2.06 (95%CI: 1.08-3.94, P=0.028). These effects were essentially additive and were independent of other classical risk factors. Other studied genes did not show significant association with coronary in-stent restenosis. CONCLUSION: In patients with coronary artery disease, the possession of the 298Asp and -786C variants of the eNOS gene are a risk factor for coronary in-stent restenosis, demonstrating the importance of the nitric oxide system in restenosis.

Analysis of Variance↗