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At least 235 records · Page 13Linked to original sources
PubMed2004

Polymorphisms of the CYP1B1 gene as risk factors for human renal cell cancer.

PURPOSE: CYP1B1 activates various environmental carcinogens in human tissues, including renal tissues. We hypothesize that certain polymorphisms of the CYP1B1 gene are risk factors for renal cell cancer. The rationale for this hypothesis is that chemical procarcinogenic compounds require metabolic activation by oxidative enzymes such as CYP1B1 to be transformed into potentially carcinogenic forms. To test this hypothesis, we investigated the genotypic distributions of six different loci on the CYP1B1 gene and their association with renal cell cancer. EXPERIMENTAL DESIGN: DNA from 211 cases of human renal cell cancer and 200 healthy controls was analyzed by sequence-specific PCR and direct DNA sequencing to determine the genotypic frequencies of six different polymorphic loci on the CYP1B1 gene. RESULTS: The results of this study demonstrate that the frequencies of genotype 119T/T and genotype 432G/G were significantly higher in renal cell cancer patients compared with healthy normal controls. The relative risks were calculated as 3.01 and 2.17 for genotypes 119T/T and 432G/G, respectively, in renal cell carcinoma patients. These genotypic distributions were also significantly different between male and female patients. The relative risks of genotype 119T/T were calculated as 3.95 in males and 1.92 in females, and the relative risks of genotype 432G/G were calculated as 2.81 in males and 1.35 in females. CONCLUSIONS: The present study demonstrates for the first time that the polymorphisms at codons 119 and 432 may be risk factors for renal cancer, especially in the male population.

Aryl Hydrocarbon Hydroxylases↗
PubMedDate not supplied

Chinese population data on the PCR-based loci HLA-DQ alpha, low-density-lipoprotein receptor, glycophorin A, hemoglobin gamma G, D7S8, and group-specific component.

Allele and genotype frequencies for six polymerase chain reaction (PCR)-based DNA genetic markers were determined in a Chinese sample population. The loci are HLA-DQ alpha, low-density-lipoprotein receptor, glycophorin A, hemoglobin gamma G, D7S8, and group-specific component. These results were obtained using the AmpliType HLA-DQ alpha forensic DNA amplification and typing kit and the AmpliType PM PCR amplification and typing kit. All loci met Hardy-Weinberg expectations and there was no evidence for association of alleles between the loci. The frequency data can be used in forensic analyses and paternity tests to estimate the frequency of a DNA profile in the Chinese population.

Alleles↗
PubMed2005

Elevated factor VII as a risk factor for recurrent fetal loss. Relationship to factor VII gene polymorphisms.

Haemostatic abnormalities can be detected in a portion of the women who have recurrent fetal loss. We measured factor VII coagulant activity (FVII:C) in 65 women with 3 or more fetal losses (recurrent cases), 31 women with one 2nd or 3rd trimester loss (late loss cases), and 81 women with only live births (controls). FVII:C was greater than 2 standard deviations above the mean for controls in 9 recurrent cases (13.8%) and 2 controls (2.5%) for an odds ratio of 6.35 (95% CI 1.32-30.52, p=0.012). In recurrent cases, mean levels were significantly higher than controls for FVII:C (p=0.003), FVII antigen (p=0.024), and FVIIa (p=0.001). Late loss cases had an odds ratio of 4.23 (95% CI 0.67-26.67, p=0.098) with FVII:C, FVII antigen, and FVIIa not significantly different from the controls. DNA was examined for the presence of mutations or polymorphisms in the promoter region of the FVII gene, using denaturing HPLC. Abnormal patterns were confirmed with direct sequencing. A previously reported polymorphism, -402 G>A, was found to be present in 11/14 subjects with elevated FVII:C (79%) and 43% of those with normal levels (p=0.029). FVII:C, FVII antigen and FVIIa varied significantly with genotype; however, genotype frequencies did not differ between controls and either case group. No other promoter polymorphisms were identified. This is the first report of a significant elevation of FVII in a population with recurrent fetal loss. These data suggest the need for further investigation of this potential risk factor.

Abortion, Habitual↗
PubMed1999

Genetic association analysis of serotonin system genes in bipolar affective disorder.

OBJECTIVE: This study examined the putative role of serotonin genes in the etiology of bipolar affective disorder. METHOD: Genetic association analysis was performed for individuals with bipolar affective disorder and unaffected subjects closely matched in age, sex, and ethnic background (N=103 in each group). The allele and genotype frequencies of polymorphisms at the genes for serotonin receptors HTR1A, HTR1Dalpha, HTR1Dbeta, HTR2A, HTR2C, HTR7, tryptophan hydroxylase (TPH), and the serotonin transporter (hSERT) were compared in the two groups of subjects. RESULTS: Statistically significant positive associations were found for HTR2A and hSERT polymorphisms. However, results from an independent replication group of over 100 patients with bipolar affective disorder and their matched comparison subjects failed to confirm these associations. CONCLUSIONS: These results suggest that the serotonin genes studied are not associated with bipolar affective disorder, although transmission disequilibrium studies are required in order to confirm this conclusion.

Adult↗
PubMed2003

Genetic variation of the APOE promoter and outcome after head injury.

The APOE-epsilon4 allele is associated with risk for Alzheimer's disease (AD) and poorer outcome after head injury. Several studies show that polymorphisms in the promoter that influence APOE expression also increase risk for AD. The authors' data from a study of 92 patients are consistent with a possible influence of the G-219T promoter polymorphism on outcome after head injury. The group with unfavorable outcome had a genotype frequency distribution similar to that found in AD.

Adolescent↗
PubMed2006

Multicapillary electrophoresis analysis of single-nucleotide sequence variations in the deoxycytidine kinase gene.

BACKGROUND: Investigation of the genetic background of complex traits is the focus of recent interest, as several common diseases or the individual response to treatments of various illnesses have not yet been explored. These studies require the development and implementation of reliable and large-scale genotyping methods. In this report, we introduce an efficient technique based on PCR-restriction fragment length sequence variation technique for the analysis of the -360CG and -201CT single-nucleotide sequence variations in the deoxycytidine kinase gene. METHODS: A multicapillary gel electrophoresis instrument was used for the size determination of the generated DNA fragments. A healthy Hungarian population of 100 individuals was investigated to determine allele and genotype frequencies for the 2 sequence variations of interest. RESULTS: We found that the occurrence of the minor allele is rather low, i.e., the frequency of both the -360G and -201T variants is 1%. CONCLUSIONS: Our technique can readily facilitate the analysis of these important sequence variations in other ethnic groups to clarify the role of these sequence variations in conjunction with arabinosylcytosine treatment in acute myeloid leukemia.

Deoxycytidine Kinase↗
PubMed2002

Polymorphisms in the lipopolysaccharide-binding protein and bactericidal/permeability-increasing protein in patients with myocardial infarction.

Gram-negative bacterial infection, namely Chlamydia pneumoniae has been recently discussed as a risk factor for myocardial infarction. The lipopolysaccharide-binding protein (LBP) and the bactericidal/permeability-increasing protein (BPI) play a role in the processes leading to recognition and neutralisation of the Chlamydia pneumoniae and their endotoxins lipopolysaccharides (LPS). LPS interact with plasma LBP, and LBP-LPS complex activates monocytes/macrophages, which can influence the atherosclerotic process. BPI is cytotoxic for Gram-negative bacteria and BPI-LPS complexes do not activate monocytes. We have analysed the polymorphisms in the LBP gene (Gly98-->Cys; Pro436-->Leu) and BPI gene (Lys216-->Glu; PstI polymorphism in intron-5; G545-->C) in 313 patients after myocardial infarction (MI) and in 302 control individuals. Genotype frequencies in the LBP gene and BPI gene did not differ between MI patients and control individuals. Our findings suggest that LBP and BPI polymorphisms do not influence the risk of MI.

Acute-Phase Proteins↗
PubMed1976

Genetics and asexual reproduction of the sea anemone Metridium senile.

1. Metridium senile was studied for phosphohexose-isomerase variation at three locations on Cape Cod, Massachusetts: Woods Hole, Cape Cod Canal, and Barnstable Town Boat Harbor. 2. All three locations exhibited significant polymorphism for PHI. 3. Mapping of individual polyps was performed at Barnstable to analyze spatial distributions of clones and genotypes. 4. In Barnstable, PHI does not depart significantly from Hardy-Weinberg expectations at the time of establishment of new polyps, and establishment of larvae is spatially random with respect to PHI genotype. 5. Asexual reproduction was uses as a meausre of the relative success of different PHI genotypes. There are indications that not all genotypes are equally likely to produce large clones. 6. There is significant heterogeneity among the three locations with respect to PHI genotype frequencies, suggesting that there may be geographical differentiation of the populations. 7. Sessile, asexual organisms provide powerful tools for examining the dynamic aspects of genetic structure in natural populations.

Animals↗
PubMed2001

Candidate gene analysis for loci affecting litter size and ovulation rate in swine.

A candidate gene approach was used to determine whether specific loci explain responses in ovulation rate (OR) and number of fully formed (FF), live (NBA), stillborn, and mummified pigs at birth observed in two lines selected for ovulation rate and litter size compared with a randomly selected control line. Line IOL was selected for an index of OR and embryonic survival for eight generations, followed by eight generations of two-stage selection for OR and litter size. Line C was selected at random for 16 generations. Line COL, derived from line C at Generation 8, underwent eight generations of two-stage selection. Lines IOL and C differed in mean EBV by 6.1 ova and 4.7 FF, whereas lines COL and C differed by 2.2 ova and 2.9 FF. Pigs of Generation 7 of two-stage selection lines were genotyped for the retinol binding protein 4 (RBP4, n = 190) and epidermal growth factor (EGF, n = 189) loci, whereas pigs of Generations 7 and 8 were genotyped for the estrogen receptor (ESR, n = 523), prolactin receptor (PRLR, n = 524), follicle-stimulating hormone beta (FSHbeta, n = 520), and prostaglandin-endoperoxide synthase 2 (PTGS2, n = 523) loci. Based on chi-square analysis for homogeneity of genotypic frequencies, distributions for PRLR, FSHbeta, and PTGS2 were different among lines (P < 0.005). Differences in gene frequencies between IOL vs C and COL vs C were 0.33 +/- 0.25 and 0.16 +/- 0.26 for PRLR, 0.35 +/- 0.20 and 0.15 +/- 0.24 for FSHbeta, and 0.16 +/- 0.16 and 0.08 +/- 0.18 for PTGS2. Although these differences are consistent with a model of selection acting on these loci, estimates of additive and dominance effects at these loci did not differ from zero (P > 0.05), and several of them had signs inconsistent with the changes in allele frequencies. We were not able to find significant associations between the polymorphic markers and phenotypes studied; however, we cannot rule out that other genetic variation within these candidate genes has an effect on the traits studied.

Animals↗
PubMed2005

Polymorphisms of high-affinity IgE receptor and histamine-related genes in patients with ASA-induced urticaria/angioedema.

The pathogenic mechanism of ASA-induced urticaria/angioedema (AIU) is still poorly understood, but it has been known that histamine releasing by cutaneous mast cell activation is considered to be an important role. Considering the importance of histamine in AIU, we speculated that a genetic abnormality of histamine-related genes such as a high-affinity IgE receptor, a metabolic enzyme of histamines and histamine receptors, may be involved in the development of AIU. Enrolled in the study were 110 patients with AIU, 53 patients without ASA hypersensitivity who had various drug allergies presenting as exanthematous skin symptoms, and 99 normal healthy controls (NC). Eleven single nucleotide polymorphisms (SNPs) of the beta chain of the high-affinity IgE receptor (FCER1B) and three histamine-related genes-histamine N-methyltransferase (HNMT), histamine H1 receptor (HRH1), histamine H2 receptor (HRH2)-were screened using the SNP-IT assay based on a single base extension method. No significant differences were observed in allele and genotype frequencies, and haplotype frequencies of all the SNPs of FCER1B, HNMT, HRH1, and HRH2 among the three groups (p>0.05, respectively). These results suggest that the polymorphisms of FCER1B and the three histamine-related genes may not contribute to the development of AIU phenotype in the Korean population.

Adult↗
PubMed2003

Polymorphism in transmembrane region of MICA gene and cholelithiasis.

AIM: To study the significance of polymorphism of MHC class I chain-related gene A (MICA) gene in patients with cholelithiasis. METHODS: Subjects included 170 unrelated adults (83 males) with cholelithiasis and 245 randomly selected unrelated adults (130 males) as controls. DNA was extracted from peripheral leukocytes and analyzed for polymorphism of 5 alleles (A4, A5, A5.1, A6 and A9) of the MICA gene. RESULTS: There was no significant difference in phenotype, allele, and genotype frequencies of any of the 5 alleles between cholelithiasis patients and controls. CONCLUSION: This study demonstrates that MICA alleles studied bear no relation to cholelithiasis.

Asian People↗
PubMed2000

[Chinese Han population data obtained from fluorescently detected STR loci-vWA31A, TH01, F13A01, FES, TPOX and CSF1PO].

OBJECTIVE: This paper was designed to evaluate 6 short tandem repeats(STR) loci for their use in forensic personal identification. METHODS: The allele frequencies and genotype frequencies at 6 tetranucleotide STR loci were determined in a sample of 132 unrelated individuals from a Chinese population of Han nationality in Guangzhou. The PCR products were analysed on 4% denaturing PAGE and detected using fluorescently labeled primers in an automated 377 sequencer(PE). The resultant allele frequencies were compared with other population or race databases. RESULTS: All the 6 loci (vWA31A, TH01, F13A01,FES, TPOX, CSF1PO) met Hardy-Weinberg equilibrium. No random association of alleles among the 6 loci was noted. Except locus vWA31A, the observed heterozygosities at other 5 loci were significantly lower than those reported in Caucasian and Black population studies. The calculated DP=0.99999,PE=0.9708,pM=1.059 times 10(-5). CONCLUSION: The data obtained can be used in human identity and paternity testing, and in other genetic researches and population investigation.

Alleles↗
PubMed2002

[The C677T mutation in the methylenetetrahydrofolate reductase gene and its association with deep vein thrombophilia in Shandong Hans].

OBJECTIVE: To study the prevalence of methylenetetrahydrofolate reductase (MTHFR) C677T genotype and its association with deep vei n thrombophilia in Chinese. METHODS: Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis was conducted to examine mutation with 63 deep vein thrombophilic patients and 80 health controls in Shandong Hans. The genotype frequencies were calculated by gene counting in patients and controls, and an analysis was made on the association of MTHFR C677T mutation with deep venous thrombosis in Shandong Hans. RESULTS: In case- controls, the frequencies of C/T heterozygote were 41.27% and 43.75%; whereas those of T/T homozygote were 52.38% and 36.25%. Significantly elevated mutation was observed in patients(Chi-square=6.372, P 0.01 OR(T/T)=4.552 95% confidence interval:1.440-14.390, Chi-square =6.742 P=0.009). CONCLUSION: The C677T mutation of methylenetetrahydrofolate reductase gene is a risk factor associated with deep vein thrombophilia in Shandong Hans.

China↗
PubMed2002

[Effects of uncoupling protein 3 gene -55 C-->T variant on lipid metabolism, body fat, its distribution and non-insulin-dependent diabetes mellitus in Chinese].

OBJECTIVE: To investigate the relationship of UCP3 gene -55 C-->T variant with lipid metabolism, body fat, its distribution and non-insulin-dependent diabetes mellitus(NIDDM) in Chinese. METHODS: Polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP) was used to detect the genotype of UCP3 gene -55 C-->T in a total of 316 Chinese including 165 individuals with normal glucose tolerance(NGT) and 151 patients with type 2 diabetes). MRI was used to detect local body fat; the enzyme method and sulfate-sephadex-manganese precipitation method were used to detect TC and HDL-C, and then LDL-C was calculated with corresponding formula. RESULTS: (1)No difference was seen on comparing allele and genotype frequencies of Chinese with those of Caucasian (P=0.1120 and P=0.0646, respectively), whereas significant difference in these frequencies was seen between Chinese and Pima Indians(P=0.0 105 and P=0.0314, respectively). (2)Stepwise regression analysis revealed that the independent variables to UCP3 gene -55 C-->T were: HDL-C(P= 0.013)and LDL-C(P=0.012) in male NGT subgroup FA(P=0.023) in female NGT subgroup TG(P=0.004)in male DM subgroup, and waist to hip ratio (WHR)(P=0)in female DM subg roup. (3)The allele frequency of DM group was significantly different from that of NGT(P =0.0358). The odd ratio for the T allele carrier with NIDDM was 1.434 (95%CI 1.031-1.995). CONCLUSION: Although UCP3 gene 55 C-->T variant is associated with lipid metabolism, body fat and its distribution in Chinese, the association is dependent on sex and disease status. The variant is also associated with NIDDM in Chinese.

Adipose Tissue↗
PubMed2002

Lack of association between atopic asthma and the tumor necrosis factor alpha-308 gene polymorphism in a Czech population.

Susceptibility to the development of asthma and other atopic diseases is known to be associated with genetic components. Several investigators have linked the tumor necrosis factor (TNF) genes and nearby markers located on chromosome 6p to atopy and asthma. A recent study has demonstrated that the TNF-alpha*2 allele of a polymorphism in the TNF-alpha gene promoter region (G-308 A) is associated with a higher risk for the development of atopy in Spanish patients. This study evaluates the possible role of two described bi-allelic polymorphisms in the TNF locus [a G to A transition at position-308 in the 5'-promoter region of the TNF-alpha gene and an NcoI restriction fragment length polymorphism (RFLP) in the first intron (+252A/G) of the LT-alpha(TNF-beta) gene] in atopic diseases in a Czech population. We investigated the distribution of these polymorphisms in a case-control study. The genotypes were determined in 151 patients with atopic asthma and 155 randomly sampled control subjects. The genotype frequencies for both polymorphisms were similar in cases and controls. No significant differences in allele frequencies were found between either of the patients groups and the reference subjects. Similarly, there were no associations of any of the examined variants of the TNF genes with total IgE, specific IgE or pulmonary function tests in patients with allergic diseases. We conclude that these polymorphisms of the TNF genes are unlikely to contribute to atopic disease risk in our population. Significant associations that have been reported in other studies may reflect the genetic heterogeneity of these complex diseases.

Adult↗
PubMed2001

[Forensic application of reverse dot blot with biotin incorporation].

A rapid and accurate reverse dot blot technique was successfully established. It could distinguish the 6 alleles of 0101, 0102, 0103, 0201, 0301 and 0401 of HLA-DQA locus. Alleles and genotype frequencies for HLA-DQA locus were determined in 200 unrelated individuals of northern Han population. The discrimination power (DP) was 0.928, heterozygocity (H) 0.75. By direct biotin incorperation, 1 ng genome DNA could be detected successfully. This method can be used for paternity test and individual identification in forensic science practice.

Alleles↗
PubMed2000

[Validation studies on the analysis of the HLA-DQA1 locus using PCR and its application in forensic science].

Validation Studies were conducted to evaluate the forensic applicability of HLA-DQA1 locus. The locus was typed by a reverse dot blot approach and allele specific oligonucleotide probes were immobilized on a nylon membrane strip. Allele and genotype frequency for HLA-DQA1 locus was determined in shanghai Han population. The frequency data can be used in individual identification and paternity test.

Alleles↗
PubMed2003

[Association of child absence epilepsy with T-STAR gene].

OBJECTIVE: To investigate the Association of child absence epilepsy with T-STAR gene. METHODS: PCR was conducted on the DNA of peripheral blood white cells from 48 children with child absence epilepsy (CAE), 47 male and 49 female, aged 2.9 approximately 14, of Han nationality in Northern China and 48 healthy children in the same area to amplify the exons of T-STAR gene The PCR products underwent sequencing to identify the possible mutations. RESULTS: No mutation was found in the exons of the T-STAR gene, however, 3 single nucleotide polymorphisms (SNPs) were found. A case-control study was carried out, using SNP1 and SNP2. There was no significant difference in genotype frequency of the 2 SNPs between the CAE group and control group (SNA1: chi(2) = 2.965, df = 1, P = 0.085; SNP2: chi(2) = 2.965, df = 1, P = 0.085). There was no significant difference in allele frequency of the 2 SNPs between the CAE group and control group too (SNA1: chi(2) = 3.185, df = 2, P = 0.203; SNP2: chi(2) = 3.185, df = 2, P = 0.203). CONCLUSION: T-STAR may not be a susceptibility gene for CAE in Chinese populations.

Adolescent↗