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At least 1,711 records · Page 95Linked to original sources
PubMed2006

Genetic polymorphisms in the MMP-1 and MMP-3 gene may contribute to chronic periodontitis in a Brazilian population.

OBJECTIVES: Matrix metalloproteinase-1 and -3 (MMP-1, MMP-3) represent proteinases that degrade macromolecules of the extracellular matrix. These enzymes play a fundamental role during destruction of periodontal tissues. Genetic polymorphisms were characterized in the promoter region of the MMP-1 and MMP-3 genes. The aim of this study was to investigate the relationship between these genetic variations with chronic periodontitis in a Brazilian population. MATERIAL AND METHODS: Non-smoking subjects (n = 114) exhibiting sites > or = 5 mm clinical attachment loss were recruited for study. Control subjects (n = 109) should not exhibit clinical signals of periodontitis. MMP-1 (-1607 1G/2G, -519 A/G) and MMP-3 (-1612 5A/6A) gene promoter polymorphisms were genotyped using PCR-RFLP methods. RESULTS: Analysis of polymorphisms showed no differences in distribution of the -1607 1G/2G and -519 A/G variants in the MMP-1 gene between the healthy and periodontitis group (p > 0.05). However, the distribution of genotype frequencies of the -1612 5A/6A polymorphism in the MMP-3 gene showed that the 5A/5A genotype was significantly more frequent in the periodontitis group (p = 0.008). The same was not observed in the 5A/6A genotype once only one 5A allele is carried. We also observed a trend to increase the frequency of the MMP-1/MMP-3 haplotype (2G/5A) in the periodontitis group (p = 0.08). CONCLUSION: On the basis of the results, no significant association is found for the MMP-1 polymorphisms with susceptibility of periodontitis, while the MMP-3 gene polymorphism may contribute to periodontal tissue destruction during periodontitis in Brazilian subjects.

Adenine↗
PubMed2002

[Individual susceptibility to hematotoxicity from benzene exposure and the genetic polymorphism of metabolic enzymes].

Benzene is one of wildly used chemicals. Long-term exposure to benzene causes hematotoxicities and further, the development of including anemia, myelodysplastic syndrome (MDS), aplastic anemia, etc., with the leukemia as the worst. People vary greatly in their susceptibility to adverse health outcomes from benzene exposure. The author reviewed the relationship between genetic polymorphism of I metabolic enzymes(CYP2E1, NQO1, MPO) and II metabolic enzymes(GST, PST) involving benzene metabolite and interindividual variation in their genetic susceptibility to hematotoxicity from benzene exposure in this paper.

Air Pollutants, Occupational↗
PubMed2006

[Genetic polymorphism of HLA-Cw locus in hematopoietic stem cell transplantation patient and donor population].

OBJECTIVE: To analyze the distribution of genes in HLA-Cw locus from Han population of China in a large scale, and to provide basic data for further study on the genetic characteristics of HLA-Cw locus of this population. METHODS: Totally 1285 unrelated Chinese Han individuals were typed by PCR-SSP, and statistics was utilized to investigate the distribution rules of detected genes. RESULTS: Twenty-three HLA-Cw alleles were identified in Chinese Han population, out of them HLA-Cw*01, *03, *07 and *08 were the commonest genes, which accounted for frequencies of 0.1529, 0.2385, 0.1747 and 0.1004, respectively. Five genes which could not be identified by serological method were deaed: HLA-Cw*12, *14, *15, *16 and *17. Hardy-Weinberg test showed that the observed genetic polymorphism distribution values were correspondent with the expected (chi-square=73.74, df=98, P>0.5). CONCLUSION: This study may serve a full-scale scientific genetic parameters of HLA-Cw genes for Chinese Han population studies.

Adolescent↗
PubMedDate not supplied

Association of the genetic polymorphism of the CYP19 intron 4[TTTA]n repeat with familial prostate cancer risk in a Japanese population.

BACKGROUND: Estrogen is crucial for development of benign prostate hyperplasia and prostate cancer. Aromatase (CYP19) is a key enzyme for estrogen synthesis in males. The genetic polymorphism of the CYP19 intron 4 [TTTA]n tetranucleotide has been studied in relation to breast cancer susceptibility. MATERIALS AND METHODS: We examined the association of the tetranucleotide repeat polymorphism of the CYP19 gene with familial prostate cancer risk in a Japanese population by performing a case-control study consisting of 99 familial prostate cancer cases and 116 normal controls. RESULTS: [TTTA] repeats ranged from 7 to 13 and were designated as A1 to A7 according to the repeat number. We did not observe any A3 allele among cases and controls, nor A7 among cases. Short repeat alleles, A1 and A2, had a tendency to be frequently observed in cases (odds ratio [OR] = 1.43, 95% confidence interval [CI] = 0.96-2.14, p = 0.080). Analysis of polymorphic genotypes showed that short genotypes, i.e., A1A1, A1A2 and A2A2, significantly increased prostate cancer risk in comparison with other longer genotypes (OR = 1.80, 95% CI = 1.04-3.11, p = 0.035). Stratification of cases according to the pathological grade or the clinical stage showed no significant differences among categories. CONCLUSIONS: In the present study, we found that short polymorphic genotypes of [TTTA]n repeats of the CYP19 gene were associated with familial prostate cancer risk.

Aged↗
PubMed2000

Genetic polymorphisms of cytochrome p4502E1 and susceptibility to alcoholic liver disease and hepatocellular carcinoma in a white population: a study and literature review, including meta-analysis.

AIMS: To investigate the associations between the Rsa I, Dra I, and Taq I genetic polymorphisms of cytochrome p4502E1 and susceptibility to alcoholic liver disease or to hepatocellular carcinoma. METHODS: DNA samples isolated from 61 patients with alcoholic liver disease, 46 patients with hepatocellular carcinoma, and 375 healthy controls were subjected to polymerase chain reaction amplification followed by digestion with the endonucleases Rsa I, Dra I, or Taq I. Meta-analysis was performed using data from previous studies of Rsa I polymorphism and the risk of alcoholic liver disease. RESULTS: No association was found between any of the three polymorphisms and susceptibility to hepatocellular carcinoma. The distributions of Rsa I and Dra I alleles among the patients with alcoholic liver disease were not significantly different from those among the control group. Meta-analysis of this data and previous data concerning Rsa I polymorphism and alcoholic liver disease risk failed to demonstrate any significant association between the two. However, the alcoholic liver disease group in this study showed a significantly lower frequency of the less common Taq I allele compared with the healthy control group (odds ratio, 0.33; 95% confidence interval, 0.12 to 0.78). CONCLUSIONS: Possession of the less common Taq I cytochrome p4502E1 allele is associated with reduced susceptibility to alcoholic liver disease. There is no existing evidence that the Taq I polymorphism is directly associated with altered alcohol metabolism, but it might be in linkage disequilibrium with as yet unidentified protective factors.

Adult↗
PubMed2005

Mapping quantitative trait loci for milk production and genetic polymorphisms of milk proteins in dairy sheep.

In this paper, we present recent advances in the molecular dissection of complex traits in dairy sheep and discuss their possible impact on breeding schemes. In the first step, we review the literature data on genetic polymorphisms and the effects of sheep alphas1-casein and beta-lactoglobulin loci. It is concluded that the results are rather inconsistent and cannot be used in dairy sheep selection. In a second step, we describe the strategy implemented in France, Italy and Spain taking advantage of the genetic maps for QTL detection. These studies were part of a European project, called "genesheepsafety", which investigated both milk production and functional traits. Preliminary QTL results are presented for production traits.

Animals↗
PubMed2004

Cytogenetic biomarkers and genetic polymorphisms.

Cytogenetic biomarkers have long been applied in surveillance of human genotoxic exposure and early effects of genotoxic carcinogens. Due to their wide use, it has been possible to evaluate, in international collaborative studies, if a high level of these biomarkers in peripheral lymphocytes is predictive of cancer risk. Thus far, such an association has been observed for chromosomal aberrations (CAs), but not for sister chromatid exchanges (SCEs) or micronuclei (MN). The cancer risk predictivity of CAs was not dependent on the time between CA analysis and cancer detection and did not appear to be explained by tobacco smoking or occupational exposure to carcinogens but was seen in unexposed non-smokers as well. This suggests a role for individual susceptibility factors. Genetic polymorphisms of various xenobiotic-metabolising enzymes, influencing the metabolic activation and detoxification of carcinogens, have been associated with cancer risk, and some of them also appear to affect cytogenetic biomarkers. The lack of glutathione S-transferase M1 (GSTM1 null genotype) is associated with increased sensitivity to genotoxicity of tobacco smoke, and GSTM1 null smokers also show an increased frequency of CAs and SCEs. N-Acetyltransferase (NAT2) slow acetylation genotype and glutathione S-transferase T1 (GSTT1) null genotype seem to elevate the baseline level of CAs and SCEs and CAs, respectively--possibly because of reduced capacity to detoxify some wide-spread or endogenous genotoxins. For some chemicals, in vitro cytogenetic studies with lymphocyte donors representing different genotypes have been able to predict a differential in vivo response. For instance, in vitro SCE induction by styrene and by epoxide metabolites of 1,3-butadiene is modified by GSTM1 and GSTT1 genotypes--which also influence the excretion of specific mercapturic acids in humans exposed to butadiene and styrene. Polymorphisms of DNA repair and folate metabolism are expected to be of special importance in modulating genotoxic effects. Some evidence exists for the effects of X-ray cross complementation group 1 (XRCC1) codon 280 and (in smokers) Xeroderma pigmentosum group D (XPD) codon 23 polymorphisms on baseline CAs, for XRCC1 codon 399 polymorphism on SCEs in smokers, and for methylene tetrahydrofolate reductase (MTHFR) codon 677 and methionine synthase reductase (MTRR) polymorphisms on spontaneous MN.

Animals↗
PubMed2006

The influence of genetic polymorphisms in Ahr, CYP1A1, CYP1A2, CYP1B1, GST M1, GST T1 and UGT1A1 on urine 1-hydroxypyrene glucuronide concentrations in healthy subjects from Rio Grande do Sul, Brazil.

Polymorphisms in genes encoding polycyclic aromatic hydrocarbon (PAH) metabolizing enzymes may alter metabolism of these carcinogens and contribute to inter-individual difference in urine concentrations. We investigated the influence of genetic polymorphism on PAH metabolism in urine from 199 healthy subjects from Southern Brazil. We measured urine 1-hydroxypyrene glucuronide (1-OHPG) concentrations using immunoaffinity chromatography and synchronous fluorescence spectroscopy and genotyped subjects using standard methods. Genetic variants in CYP1B1 (rs1056827, rs1800440, rs10012) were strongly associated with urine 1-OHPG with P-values < 0.010. Variants in aryl hydrocarbon receptor (Ahr) (rs4986826), CYP1A1 (rs1799814) and CYP1A2 (rs2069514) were also, although less strongly, associated with changes in urine 1-OHPG concentrations. These variants had P-values of 0.074, 0.040 and 0.025, respectively. The median urine 1-OHPG concentrations (pmol/ml) in the homozygous wild-type and homozygous variants for CYP1B1 (rs10012) and the Ahr, CYP1A1 and CYP1A2 variants listed above were 2.16 and 0.10, 2.16 and 0.41, 2.03 and 0.46, 2.19 and 2.79, respectively. We found no effect of deletions in GST M1 or GST T1, or different alleles of UGT1A1*28. Adjusting for age, sex, place of residence, tobacco smoke exposure, maté drinking, cachaça and barbeque preparation had only a minor impact on the associations. A model containing just exposure variables had an r2 of 0.21; a model with single genotypes for Ahr, CYP1A1, CYP1A2 and CYP1B1 had an r2 of 0.10; and a model combining both exposure and genotype information had a total r2 of 0.33. Our results suggest that CYP1B1 genotypes are strongly associated with urine 1-OHPG concentrations in this population.

Aryl Hydrocarbon Hydroxylases↗
PubMed1991

[Genetic polymorphism in the Karelian population].

Distribution of the genetic markers of blood groups (AB0, MNSs, Rhesus, P, Lewis, Duffy, Kell-Cellano, Kell-Kp, Kell-Sutter, Kidd, Lutheran); of serum proteins (Hp, Tf, Gc, C'3, Pi); red-cell enzymes (6-PGD, EsD, GLO, AcP, subtypes of PGM) was studied in Karels from the South part of Karelian ASSR. The results of comparison of Karels with the other finno-ugric peoples revealed peculiarities of gene pool in Karelian population.

Adult↗
PubMedDate not supplied

Association of genetic polymorphisms of glutathione-S-transferase genes (GSTM1, GSTT1 and GSTP1) with familial prostate cancer risk in a Japanese population.

BACKGROUND: Glutathione-S-transferases (GSTs) are active in the detoxification of a wide variety of toxins and carcinogens. The genetic polymorphisms of GSTM1, GSTT1 and GSTP1 genes have been studied to estimate the relative risk of various cancers. In the current study, we examined the association of the GST gene polymorphisms with familial prostate cancer in a Japanese population by performing a case-control study consisting of 81 familial prostate cancer cases and 105 normal controls. MATERIALS AND METHODS: No significant association of the GSTM1 and GSTT1 gene polymorphisms with familial prostate cancer risk was found; however, the Val/Val genotype of the GSTP1 gene significantly increased risk (OR = 9.31, 95% CI = 0.47-184, p = 0.030). The combination analysis of genotypes of the three genes showed that presence of two high-risk genotypes, i.e., null genotype of the GSTM1 or GSTT1 gene, or any Val genotypes of the GSP1 gene, significantly increased the risk of prostate cancer (OR = 2.67, 95% CI = 1.08-6.59, p = 0.03). Stratification of cases according to the pathological grade or the clinical stage showed no significant differences among categories. CONCLUSION: In the present study, we found that genotypes of GSTs, especially the Val-allele of the GSTP1 gene and the combination of three genotypes, were associated with familial prostate cancer risk.

Aged↗
PubMed2005

The porA pseudogene of Neisseria gonorrhoeae--low level of genetic polymorphism and a few, mainly identical, inactivating mutations.

N. meningitidis is the only Neisseria species known to express two outer membrane porins, PorA and PorB. However, a porA pseudogene has been identified in N. gonorrhoeae. The present study investigated the prevalence and genetic polymorphism of this porA pseudogene in 87 different N. gonorrhoeae strains. The porA pseudogene was identified in all isolates. The pseudogene comprised 12 (5.5%), of which 10 were located in the promoter spacer, and 11 (1.0%) polymorphic nucleotide sites in the upstream segment containing the promoter region, i.e. the putative -10 and -35 sequences and the promoter spacer in-between, and the hypothetical PorA coding sequence, respectively. A phylogenetic analysis of the upstream segment and the hypothetical coding sequence identified 36 sequence variants, of which 30 were not previously described. All strains comprised at least two identical confirmed inactivating deletions, of which one was located in the promoter region and one in the hypothetical PorA coding sequence. In conclusion, the porA pseudogene and its few inactivating mutations are widespread in the N. gonorrhoeae population and the homology with the N. meningitidis porA gene reflects their common evolutionary origin. The highly conserved N. gonorrhoeae porA pseudogene may reflect an evolutionary neutral molecular clock and may be a suitable genetic target for diagnosis of N. gonorrhoeae.

Base Sequence↗
PubMed2006

Interaction of genetic polymorphisms in cytochrome P450 2E1 and glutathione S-transferase M1 to breast cancer in Taiwanese woman without smoking and drinking habits.

P450 (CYP) and glutathione S-transferase (GST) are involved in the activation and detoxification of many potential carcinogens. Although, the interaction between environmental exposure and genetic polymorphisms of cytochrome P450 2E1 (CYP2E1) and glutathione S-transferase M1 (GSTM1) in breast cancer has been assessed, the gene-gene interactions between CYP2E1 and GSTM1 related to breast cancer have not been focused on and reported. We conducted a hospital-based case-control study to investigate whether the genetic interaction effects of CYP2E1 and GSTM1 modify the risk of developing breast cancer independent of the effect of cigarette smoking and alcohol consumption. Individuals with the C2/C2 genotype of CYP2E1 had a lower risk (OR = 0.24, 95% CI = 0.08-0.74) when compared with those with the C1/C1 genotype. However, there was no significant difference (OR = 1.05, 95% CI = 0.73-1.50) in the GSTM1 genotype frequency between the cases with breast cancer and that of the controls. When individuals with the genotype of C1/C1 or C1/C2 of CYP2E1 and the wild-type of GSTM1 were compared with those of C2/C2 of CYP2E1 and the null-type of GSTM1 however, we found a significantly increased risk (OR = 3.50, 95% CI = 1.01-16.55) in the breast cancer patients. Our findings indicated a gene-gene interaction between CYP2E1 and GSTM1 was accessible to developing breast cancer in Taiwanese women without the habits of cigarette smoking and alcohol consumption even though independent effects of CYP2E1 and GSTM1 were weak or non-significant and suggest that environmental carcinogen besides cigarette and alcohol consumption could induce breast cancer.

Alcohol Drinking↗
PubMed2003

Platinum/paclitaxel-based chemotherapy in advanced ovarian carcinoma: glutathione S-transferase genetic polymorphisms as predictive biomarkers of disease outcome.

BACKGROUND: The glutathione S-transferases (GSTs) are a group of multifunctional enzymes that catalyze the conjugation of glutathione with a variety of electrophilic compounds, including cytotoxic agents. A significant percentage of normal individuals exhibit genetic polymorphism with a homozygous deletion (null genotype) of the genes, leading to absence of the enzyme. METHODS: In the present study we analyzed GSTM1 and GSTT1 polymorphisms in the genomic DNA isolated from peripheral blood of patients with ovarian cancer treated with chemotherapy (paclitaxel and cisplatinum) after cytoreductive surgery and assessed its correlation with the clinical outcome of these patients. The median follow-up for the patients was 30 months. RESULTS: The estimated 3-year survival rate was 59.8% for all patients and 20.8% for carriers of GSTM1-wt/GSTT1-wt (wt indicates wild type) genotype combination (37.7% for GSTM1-wt alone) compared with 83.1% for non-GSTM1-wt/GSTT1-wt genotype carriers (100% for GSTM1-null). The mean survival time was significantly better in patients who are carriers of the GSTM1-null genotype (40.5 vs. 33.5; P=0.006) or carriers of non-GSTM1-wt/ GSTT1-wt genotypes (55.4 vs. 30.7; P=0.009). The progression-free interval was more favorable for GSTM1-null carriers (41.9 vs. 27.4; P=0.024). CONCLUSION: The study suggests that characterization of the drug-metabolizing genetic individual profile can be of great interest in clinical oncology. It can define the optimal chemotherapy for each patient, improve the efficiency, and reduce the incidence of drug toxicity and poor drug responses.

Adenocarcinoma↗
PubMed2003

Methionine synthase genetic polymorphism MS A2756G alters susceptibility to follicular but not diffuse large B-cell non-Hodgkin's lymphoma or multiple myeloma.

Lymphoproliferative diseases are characterized by chromosomal aberrations, and susceptibility may depend on inherited activity of enzymes required for DNA synthesis and methylation. We analysed genetic polymorphisms for methionine synthase (MS) A2756G, methylenetetrahydrofolate reductase (MTHFR) C677T and MTHFR A1298C in Caucasians with non-Hodgkin's lymphoma (NHL; n = 151), multiple myeloma (MM; n = 90) and 299 control subjects. The MS 2756 AG/GG genotypes were significantly under-represented in NHL (26.2%) vs control subjects (37.2%; P = 0.02), and conferred a 2.4-fold lower risk of follicular (odds ratio = 0.41, 95% confidence interval: 0.19-0.88, p = 0.02) but not diffuse large B-cell lymphoma. MM patients showed no significant difference in the polymorphisms compared with control subjects.

5-Methyltetrahydrofolate-Homocysteine S-Methyltran↗
PubMedDate not supplied

Genetic polymorphism of manganese superoxide dismutase (MnSOD) and breast cancer susceptibility.

Within mitochondria, manganese superoxide dismutase (MnSOD) provides a major defence against oxidative damage by reactive oxygen species (ROS). An alanine-9valine (Ala-9Val) polymorphism in the mitochondrial targeting sequence of MnSOD has been described and has recently been associated with risk of human breast cancer. Our present case-control study was performed to explore the association between MnSOD genetic polymorphism and individual susceptibility to breast cancer. Ala-9Val polymorphism in the signal sequence of the protein for MnSOD was determined using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay in a study population. There was no significant difference in risk for breast cancer development between patients positive and negative for the MnSOD Ala allele with adjusted odds ratio (OR): 0.86 (95% confidence interval (CI(0.43 to 1.72). When MnSOD Ala was combined with either cytochrome P450 1B1 CYP1B1*1 and catechol O-methyltransferase COMT-L (V158M) genotypes, the risk for developing breast cancer was significantly increased in patients with a body mass index (BMI) greater than 24 kg m(-2) (OR: 1.42 (95%CI=1.04-1.93)).

Alleles↗
PubMed2003

Genetic polymorphisms of the beta-2 adrenergic receptor in Israelis with severe asthma compared to non-asthmatic Israelis.

BACKGROUND: It has been argued that arginine replacement in locus 16 (Arg16) of beta 2 adrenergic receptor with glycin (Gly16) increases asthma severity, while glutamin replacement in locus 27 (Gln27) with glutamic acid (Glu27) decreases it. In addition, ethnic dependency of these polymorphisms has been described, but few studies investigated its relation to asthma severity in a non-anglosaxic population. OBJECTIVES: To investigate non-anglosaxic ethnic influences on beta 2AR polymorphisms and its correlations to asthma severity. METHODS: Sixty-six Israeli Jewish and Arab asthmatics who had near-fatal asthma and/or severe nocturnal asthma and/or steroid-dependency were investigated for genetic polymorphisms of beta 2AR and compared to matched controls. The Jewish patients included both Ashkenazi (of European origin) and non-Ashkenazi (originating from the Middle East or North Africa). The results were compared with those of ethnically matched 113 non-asthmatic Israelis and non-asthmatic Anglo-Saxons described in the literature. RESULTS: We found no significant genetic differences between the asthmatics and their controls or between the various ethnic groups of our population. However, the prevalence of Glu27 was significantly lower in non-asthmatic Israelis compared to non-asthmatic Anglo-Saxons. CONCLUSIONS: The genetic distribution of beta 2AR polymorphisms in severe Israeli asthmatics is not different from that of non-asthmatic Israelis and therefore its clinical impact on asthma is probably minimal.

Adolescent↗
PubMed1980

Two-dimensional gel electrophoresis of sheep plasma proteins: genetic polymorphism of an alphal-protease inhibitor and a post-transferrin.

Two-dimensional electrophoretic analysis of sheep plasma proteins was performed by a first-dimension separation in agarose gel (pH 5.0) followed by a second-dimension one in horizontal polyacrylamide gel (pH 9.0). This method resulted in improved and reproducible separation of many alpha- and beta-globulins. Two groups of alpha 1-globulins, designated Pi-1 and Pi-2, were found to be protease inhibitors. These two inhibitors differed from each other in protease inhibitory spectra. Genetic polymorphism was observed for the Pi-2 protein and another unidentified protein, tentatively designated as post-transferrin (Ptf). Family data supported the hypothesis that Pi-2 and Ptf types were controlled by codominant, autosomal alleles. Three Pi-2 alleles and two Ptf alleles were observed in one population of the Gotland breed of sheep. The analysis of data from 50 informative matings showed no evidence of genetic linkage between the Pi-2, Ptf and transferrin (Tf) loci in the population of sheep studied.

Alleles↗