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At least 163 records · Page 9Linked to original sources
PubMed2004

Association of FAS (TNFRSF6)-670 gene polymorphism with villous atrophy in coeliac disease.

AIM: To investigate the association of FAS gene polymorphism with coeliac disease (CD) development. METHODS: FAS-G670A gene polymorphism, located in a gamma interferon activation site, was studied in 146 unrelated CD patients and 203 healthy ethnically matched controls. The restriction fragment length polymorphism (RFLP) method was used to identify FAS-G670A gene polymorphism. RESULTS: No significant difference was found in genotype frequency between CD cases and controls. In controls, however, the frequency of the GG genotype was significantly higher in women (26.5%) than in men (12.8%) (OR= 2.44, 95% CI 1.15-5.20, P=0.020) and it was also higher in men with CD than controls (OR=2.60, 95% CI 0.96-7.05, P=0.061). The GG genotype frequency was significantly higher in patients with most severe villous atrophy (Marsh IIIc lesions) (OR=3.74, 95% CI 1.19-11.82, P=0.025). A significantly less proportion of men suffered from Marsh IIIc lesions than women (OR=0.20, 95% CI 0.06-0.68, P=0.01). The risk of having severe villous atrophy increased with the additive effect of the G allele in women (P=0.027 for trend, age and gender adjusted). CONCLUSION: FAS-G670A gene polymorphism is associated with the severity of villous atrophy in CD. Female gender is also associated with the severity of villous atrophy.

Atrophy↗
PubMed2006

[Study on association between vitamin D receptor gene polymorphisms and the outcomes of HBV infection].

OBJECTIVE: To explore whether the vitamin D receptor gene (VDR) polymorphisms are associated with the outcomes of hepatitis B virus (HBV) infection in Chinese Han population. METHODS: Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to detect the polymorphisms of Fok I locus in exon 2 and Taq I locus in exon 9 of VDR gene. One hundred and eighty-four chronic hepatitis B patients and 205 asymptomatic HBV carriers were recruited to make the comparison of frequencies of genotype and haplotype of the VDR gene between the patients and the carriers. RESULTS: The univariate analysis showed a significant difference in Fok I polymorphism between chronic hepatitis B patients group and asymptomatic HBV carriers group. The FF genotype frequency in chronic hepatitis B patients group was 44.6%,higher than 31.7% in asymptomatic HBV carriers group (P<0.05). After adjusting the confounders by multiple logistic regression analysis, the result still showed a significant difference in Fok I site polymorphism between chronic hepatitis B patients group and asymptomatic HBV carriers group (OR=1.95, P<0.05). The FT haplotype frequency in chronic hepatitis B patients group was higher than that in asymptomatic HBV carriers group (OR=1.45, P<0.05). The fT haplotype frequency in chronic hepatitis B patients group was lower than that in asymptomatic HBV carriers group (OR=0.72, P<0.05). CONCLUSION: VDR gene polymorphism may be an influence factor of genetic susceptibility to HBV infection.

Gene Frequency↗
PubMed1990

Restriction site polymorphisms at the human HepG2 glucose transporter gene locus in Caucasian and west Indian subjects with non-insulin-dependent diabetes mellitus.

Digestion of human genomic DNA with the restriction enzyme StuI revealed a 2-allele polymorphism with a human HepG2 glucose transporter probe. Bands of 3.2 kilobases (kb; S1 allele) and 2.6 kb (S2 allele) were observed. The genotype frequencies were investigated in 2 non-insulin-dependent diabetic populations. The genotype frequencies of S1S1, S1S2 and S2S2 were 6, 42 and 52% among Caucasian diabetic subjects (n = 48), and 11, 38 and 51% in 47 controls, respectively. In West Indian diabetic patients (n = 48), the genotype frequencies were 17, 54 and 29%, and for 36 controls they were 25, 33 and 42%, respectively. The polymorphism information content of this restriction fragment length polymorphism (RFLP) is 0.32 in Caucasians and 0.37 in West Indians, respectively. There was no significant difference of allele or genotype frequencies between the diabetic patients and non-diabetic controls in either group. Haplotype analysis of the StuI and XbaI RFLPs showed that there was also no significant difference in the frequencies of the four different haplotypes S1X1, S1X2, S2X1 and S2X2 between the patients and controls. However, there was a difference for the frequency of the S1 allele between Caucasians (controls 30%, patients 27%) and West Indians (controls 42%, patients 44%). There was also a significant difference in the frequency of haplotype S2X2 between these two racial groups (controls 48%, cases 51% for Caucasians, and controls 33%, cases 22% for West Indians).

Alleles↗
PubMedDate not supplied

NAT2 gene polymorphism in bladder cancer: a study from North India.

PURPOSE: This study was conducted to examine: 1) whether the NAT2 genotypes are risk factors for bladder cancer, 2) to study possible association of tobacco usage with NAT2 genotype of these patients. MATERIALS AND METHODS: This case control study was undertaken over a period of 19 months and included 101 bladder cancer patients and 110 controls. The NAT2 genotypes were identified by PCR-RFLP method in peripheral blood DNA samples. Genotypes frequencies and the association of the genotypes among patients and controls group were assessed by Chi2 test and Fisher exact test. RESULTS: The NAT2 fast acetylator genotype frequency of slow or fast acetylator genotypes was not significant in bladder cancer patients alone (OR = 1.18, 95% CI: 0.69 - 2.03, p value = 0.583) or combination with tobacco users (OR = 0.84, 95% CI: 0.328 - 2.125, p value = 0.813) when compared with controls. CONCLUSION: These data demonstrate that the NAT2 fast or slow acetylators genotype did not associated with the risk of developing bladder cancer in North Indian population when compared with controls.

Adolescent↗
PubMed2007

The association between hyperuricemia and the Trp64Arg polymorphism of the beta-3 adrenergic receptor.

The object of this study was to determine the association of Trp64Arg polymorphism with hyperuricemia. This study is an age-matched, case-controlled study of 203 hyperuricemic and 203 normouricemic men. The frequency of genotypes was compared between the two groups. Possible confounding metabolic variables were included in a multiple logistic regression model for multivariate adjustment. The genotype frequencies of Trp64Trp, Trp64Arg, and Arg64Arg in hyperuricemic and normouricemic groups are respectively 130, 69, and 4 (64.0%, 34.0%, 2.0%) and 154, 45, and 4 (75.9%, 22.2%, 2.0%) (P = 0.029, Chi-square test). Simple logistic regression analysis indicated that the Trp64Arg genotype is significantly associated with hyperuricemia (OR = 1.816, 95% CI (1.167-2.827), P = 0.008). Multivariate analysis for controlling metabolic effects also showed a significant association with the occurrence of hyperuricemia (OR = 1.937, 95% CI (1.149-3.266), P = 0.013). Trp64Arg polymorphism of the beta-3 adrenergic receptor may be independently associated with hyperuricemia in males.

Adult↗
PubMed1994

Polymorphisms of the prion protein gene in Italian patients with Creutzfeldt-Jakob disease.

Creutzfeldt-Jakob disease (CJD) is a transmissible neurodegenerative disorder characterized by the accumulation of the amyloid protein PrP in the CNS. Two coding polymorphisms of the PrP gene (PRNP) are a methionine (Met) to valine (Val) change at codon 129, and a deletion in the octapeptide coding region. In the United Kingdom, homozygosity at codon 129 appears to be associated with a predisposition to develop CJD. However, in Japan, where allelic frequencies and genotype distribution are significantly different, such an association has not been demonstrated. To determine whether such deletion(s) or codon 129 polymorphisms of PRNP predispose to the development of CJD in Italian patients, 31 sporadic CJD patients with no known PRNP mutations, and 186 unrelated control subjects were studied. Genotypic frequencies at codon 129 in these Italian CJD patients revealed a significant excess of methionine alleles, and a different genotype distribution in comparison with the normal Italian population. Deletions of a 24-bp segment located in the PrP octapeptide coding region were found in two control subjects, but in none of the sporadic CJD patients. These data suggest that Met homozygosity at codon 129 may contribute, with other environmental or endogenous factors, to CJD development.

Adult↗
PubMedDate not supplied

Linkage disequilibrium in MNSs blood group system in population of south Backa.

Linkage disequilibrium is a characteristic of MNSs blood group system which performs more frequent association of linked alleles than it is expected in comparison with their allelic frequencies. Measure of linkage disequilibrium is the difference between expected and actual genotypic frequencies which is stated in coefficient of linkage disequilibrium. The purpose of this study was to fortify existence of linkage disequilibrium phenomenon inside MNSs blood group system in population of South Backa in comparison with calculated allelic frequencies. Blood group typing in MNSs system included 1,000 healthy nonrelated persons where allelic frequencies, expected and actual genotype frequencies had been calculated, as well as the differences between them. Results of investigation showed that allele has the highest allelic frequency (0.672), S allele has the lowest frequency (0.33), the highest expected frequencies are calculated for Ms/Ns (Ms/NS) (0.218) and Ms/Ns (0.2235) genotypes, while the actual frequencies are highest for MS/NS (Ms/NS) (0.184), Ms/Ns (0.193) and Ns/Ns (0.153) genotypes. Statistically significant difference between expected and actual genotypic frequencies occurs for Ms/MS and Ns/Ns genotypes, which means that S and M and N and s alleles are more frequently associated and prove the existence of linkage disequilibrium phenomenon in population of South Backa.

Adult↗
PubMed2004

Historical and contemporary multilocus population structure of Ascochyta rabiei (teleomorph: Didymella rabiei) in the Pacific Northwest of the United States.

The historical and contemporary population genetic structure of the chickpea Ascochyta blight pathogen, Ascochyta rabiei (teleomorph: Didymella rabiei), was determined in the US Pacific Northwest (PNW) using 17 putative AFLP loci, four genetically characterized, sequence-tagged microsatellite loci (STMS) and the mating type locus (MAT). A single multilocus genotype of A. rabiei (MAT1-1) was detected in 1983, which represented the first recorded appearance of Ascochyta blight of chickpea in the PNW. During the following year many additional alleles, including the other mating type allele (MAT1-2), were detected. By 1987, all alleles currently found in the PNW had been introduced. Highly significant genetic differentiation was detected among contemporary subpopulations from different hosts and geographical locations indicating restricted gene flow and/or genetic drift occurring within and among subpopulations and possible selection by host cultivar. Two distinct populations were inferred with high posterior probability which correlated to host of origin and date of sample using Bayesian model-based population structure analyses of multilocus genotypes. Allele frequencies, genotype distributions and population assignment probabilities were significantly different between the historical and contemporary samples of isolates and between isolates sampled from a resistance screening nursery and those sampled from commercial chickpea fields. A random mating model could not be rejected in any subpopulation, indicating the importance of the sexual stage of the fungus both as a source of primary inoculum for Ascochyta blight epidemics and potentially adaptive genotypic diversity.

Ascomycota↗
PubMed2007

Association of interleukin (IL)-4 intron-3 and IL-6 -174 G/C gene polymorphism with susceptibility to end-stage renal disease.

Earlier studies suggest that end-stage renal disease (ESRD) is associated with inflammatory state and have become a major cause of morbidity and mortality worldwide. This study speculated the role of interleukins (IL)-2, -4, and -6 cytokines gene polymorphism with risk of susceptibility to ESRD. Polymorphism in IL-2 (-330 T/G, polymerase chain reaction [PCR]-restriction fragment length polymorphism), IL-4 (intron-3, variable number of tandem repeat, variable number tandem repeats analysis), and IL-6 (-174 G/C, amplification refractory mutation system, i.e. ARMS-PCR) were genotyped in 193 ESRD patients and 180 controls. Significant difference was observed in genotype frequencies of IL-4 and IL-6 between ESRD patients and control group (p<0.001 and p=0.032, respectively). Patients had higher frequency of homozygous B2B2 genotype (IL-4) than controls (62.7% vs 46.7) and GG genotype of IL-6 (73.1% vs 60.6%). The genotypic frequencies of IL-2 were comparable in patients and controls (p=0.102). Significant association of IL-4 was also observed in patients with glomerulonephritis (p=0.001). Combination of low IL-4 and high IL-6 genotypes were significantly associated with ESRD showing the highest risk, i.e. >threefolds risk (odds ratio=3.48, 95%CI=1.88-6.42; p < 0.001) among the four possible combinations taking high IL-4 and low IL-6 as reference. Our study suggests that polymorphism in IL-4 and IL-6 may be associated with susceptibility to ESRD. Further, combined analysis implicated a higher risk in ESRD patients with low IL-4 and high IL-6 producing genotypes. This study provided the basis for defined anti-inflammatory approaches to limit renal disease progression.

Adolescent↗
PubMed2002

Association of beta-fibrinogen and factor VII polymorphism with plasma fibrinogen and factor VII levels, and no association of PAI-1 polymorphism with plasma PAI-1 levels in hemodialysis patients.

AIMS: Recent studies have stressed the roles of genetic factors on the plasma levels of hemostatic markers and on cardiovascular complications. We investigated the association of DNA polymorphisms for beta-fibrinogen, factor VII, and PAI-1 with plasma levels of these factors and with ischemic heart disease (IHD) and cerebral infarction (CI) in patients undergoing hemodialysis (HD). METHODS: beta-fibrinogen G/A-455, factor VII R353Q and PAI-1 4G/5G polymorphisms were determined by PCR-RFLP in 149 HD patients and in 100 controls. The plasma levels of fibrinogen, factor VII and PAI-1 were also measured. RESULTS: The allele frequencies and the genotype frequencies of these 3 polymorphisms were not different between HD patients and controls. In HD patients, plasma fibrinogen levels were significantly lower in the GG genotype than in the GA genotype, and plasma factor VII activity was significantly higher in the RR genotype than in the RQ genotype. Multiple regression analysis disclosed that CRP and beta-fibrinogen polymorphism were the significant determinants of fibrinogen levels. Plasma PAI-1 levels were not different among the 3 genotypes. The frequency of the A-455 allele was significantly higher in HD patients with CI than in those without CI, and the genotype distribution for beta-fibrinogen differed significantly between the 2 groups. Between the same 2 groups, however, significant differences were found neither in the frequency of the 353Q or 4G allele nor in the genotype distribution for factor VII and PAI-1. No significant differences in the frequency of the G-455, 353Q or 4G alleles, or in the genotype distribution for beta-fibrinogen, factor VII and PAI-1 were observed between patients with IHD and those without IHD. Multiple logistic regression analysis demonstrated that neither polymorphism was associated with CI or IHD. CONCLUSIONS: In HD patients, beta-fibrinogen and factor VII polymorphisms affected plasma levels of fibrinogen and factor VII, respectively. Beta-fibrinogen polymorphism was not an independent but a possible risk factor for CI in HD patients. Further study will be needed to confirm the precise role of 5-fibrinogen polymorphisms in the pathogenesis of CI in HD patients.

Adult↗
PubMed2005

Investigation of genetic variants of genes of the hemochromatosis pathway and their role in breast cancer.

Iron overload has been noticed as a feature of human breast cancer. Cellular iron uptake is regulated by the hemochromatosis and transferrin receptor system, mutations of which cause the iron storage disease hereditary hemochromatosis. To understand the role of hemochromatosis and transferrin receptor system mutations in breast cancer, we analyzed 19 sequence variations at HFE, TFR1, TFR2, and FPN1 and compared genotype frequencies between cases and controls in a German population. There were 688 breast cancer patients and 724 population-based and age-matched controls. For genotyping, we applied the Hemochromatosis Strip Assay and TaqMan allelic discrimination analyses. In addition to genotype frequencies, we established frequencies of compound genotypes. The frequencies of HFE at His63Asp, Ser65Cys, and Cys282Tyr, and of TFR1 at Ser142Gly minor alleles in this German population were 15.9%, 1.8%, 5.6%, and 46.0%, respectively. No rare variants at 15 more loci at HFE, TFR2, and FPN1 were observed in breast cancer patients. There were no significant differences of allele and genotype frequencies between cases and controls. Triple and quadruple compound genotypes at HFE_His63_Cys282-TFR1_Ser142Gly and HFE_His63_Ser65_Cys282-TFR1_Ser142Gly showed a nonsignificant increase in cases. Although limited by low numbers, an increased prevalence of the HFE Tyr282 minor allele was observed in breast cancer cases with a high number of affected lymph nodes (P = 0.032). Our data suggest that variants of the hemochromatosis-transferrin receptor system have no direct effect on the incidence of breast cancer in Germany. Possible effects on tumor progression and prognosis remain elusive.

Adult↗
PubMed2005

[Genetic polymorphisms of nucleotide repair gene hMTH1 in southern Chinese Han population].

In order to study the genetic polymorphisms of nucleotide repair gene hMTH1 in southern Chinese Han population, the polymorphisms of the gene's promoter and its five exons among peripheral blood lymphocytes of 172 Chinese Han people were analyzed with polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and DNA sequencing. The sequences of the promoter and exon 1 of hMTH1 gene were conserved. A T to C polymorphism was detected at the 73th base in exon 2. The genotype frequencies of TT and TC were 93.02% and 6.98%, respectively. The allelic frequencies of T and C were 96.51% and 3.49%, respectively. A T to C polymorphism was detected at codon 45 in exon 3, which was first reported. The genotype frequencies of TT and TC were 95.35% and 4.65%, respectively. The allelic frequencies of T and C were 97.67% and 2.33%, respectively. A G to A polymorphism was detected at codon 83 in exon 4. The genotype frequencies of GG and GA were 89.53% and 10.47%, respectively. The allelic frequencies of G and A were 94.77% and 5.23%, respectively. A C to T polymorphism was detected at codon 119 in exon 5. The genotype frequencies of CC and CT were 95.93% and 4.07%, respectively. The allelic frequencies of C and T were 97.97% and 2.03%, respectively.

Asian People↗
PubMed2004

Moment estimation of population diversity and genetic distance from data on recessive markers.

A moment-based method for estimating a measure of population diversity, theta or Wright's FST, is given for dominant markers such as amplified fragment length polymorphisms (AFLPs) or RAPDs in noninbred populations. Basic assumptions are that there is random mating, Hardy-Weinberg equilibrium, linkage equilibrium, no mutation from common ancestor and equally distant populations. It is based on the variances between and within populations of genotype frequencies, whereas previously moment methods for dominant markers have been indirect in that they have been based on first estimating allele frequencies and then using the variances of those frequencies. The use of genotype frequencies directly appears to be more robust. Approximate sampling errors of the estimates are given. Methods are extended to estimate genetic distances and their sampling errors. The AFLP data from samples of breeds of pig are used for illustration.

Analysis of Variance↗
PubMed2005

[Association between familial febrile convulsions and HCN2 gene].

OBJECTIVE: To investigate the possible association of familial febrile convulsions with HCN2 gene. METHODS: PCR was conducted on the DNA of peripheral blood white cells from 60 children with familial febrile convulsion (FC) of Han nationality population in northern China aged 1.5 +/- 1.0 (8 months to 5 years old), to amplify the exons of HCN2 gene. The PCR products underwent sequencing to identify the possible mutations. 101 normal children from the same area were used as controls. RESULTS: No mutation was found in the exons of HCN2 gene, however, 14 single nucleotide polymorphisms (SNPs) were found among which there were 8 newly identified SNPs. Using 9 SNPs as markers, association study was conducted between the FC group and control group. There were no significant differences in allele frequencies and genotype frequencies of the 9 SNPs between the FC group and control group. CONCLUSION: HCN2 may not be a susceptibility gene for FC in Chinese population.

Alleles↗
PubMed2000

Association analysis of 5HT transporter gene in bipolar disorder in the Indian population.

A variable number tandem repeat (VNTR) polymorphism consisting of multiple copies of a 17-bp repeat in the second intron of the serotonin transporter gene (SERT) has been reported. Different alleles of this VNTR have been found to be associated with bipolar disorder and schizophrenia. These findings have been confirmed in some populations, but disconfirmed in others. Furthermore, significant ethnic variations in the distribution of these alleles both in normal and patient populations also have been reported. We analyzed the VNTR polymorphism in 50 Indian patients with bipolar disorder and in ethnically matched controls. Two alleles corresponding to 10 and 12 repeats of the VNTR were found in both groups. There were no significant differences either in allele frequency or genotype frequency between the two groups. The nine-repeat allele that has been reported in Japanese and Caucasian populations was absent in our sample. Although it will be important to extend the present study in a larger sample, our initial results do not suggest any large association with alleles of the VNTR in the SERT gene and bipolar disorder in Indian patients. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 96:170-172, 2000.

Alleles↗
PubMed2004

Screening for C677T and A1298C MTHFR polymorphisms in patients with epilepsy and risk of hyperhomocysteinemia.

Hyperhomocysteinemia can result from decreased methylenetetrahydrofolate reductase (MTHFR) enzyme activity, owing to genetic polymorphisms andor inadequate folate intake. This study was aimed at investigating the prevalence of C677T and A1298C MTHFR polymorphisms, and their impact on hyperhomocysteinemia in 95 epileptic patients and 98 controls. Double gradient-denaturing gradient gel electrophoresis screening revealed that the frequency of T677 polymorphic allele was similar between cases and controls (46.3% vs 42.3%), whereas that of C1298 allele was significantly higher in patients (30.5% vs 19.4%, p < 0.05). Significant differences between the two groups were also found for the frequencies of genotypes AA1298 (46.3% in cases vs 67.3% in controls, p < 0.01) and AC1298 (46.3% in cases vs 26.6% in controls, p < 0.01). Other genotype frequencies did not show any statistically significant differences. Haplotype frequencies significantly differed between the two groups. The CT677/AC1298 diplotype was significantly more frequent in epileptic patients than in controls (32.6% vs 18.4%, p < 0.05). Patients treated with enzyme-inducing antiepileptic drugs, having this diplotype and concomitant low folate concentration (i.e., < 3.4 nmol/L), exhibited plasma homocysteine levels significantly higher than normal values (27.1 +/- 2.44 micromol/L, p < 0.001). This increase, however, was lower than that observed in folate-deficient patients with diplotype TT677/AA1298 (41.3 +/- 3.41 micromol/L, p < 0.001). Indeed, these two diplotypes could be regarded as risk factors for hyperhomocysteinemia. Conversely, we found that the CC677/AA1298 diplotype was significantly more frequent in controls (p < 0.01), suggesting a protective role. Our study suggests that both C677T and A1298C MTHFR polymorphisms should be examined when assessing genetic risk factors of hyperhomocysteinemia in epilepsy.

Adolescent↗
PubMed1996

No evidence of association between structural polymorphism at the dopamine D3 receptor locus and alcoholism in the Japanese.

Dopaminergic systems mediate reward mechanisms and are involved in reinforcing self-administration of dependence-forming substances, including alcohol. Studies have reported that polymorphisms of the dopamine D2 receptor, whose structure and function are similar to those of the dopamine D3 receptor, increase the susceptibility to alcoholism. These observations led to the examination of the possible association between a structural polymorphism of the D3 receptor gene and alcoholism. Genotyping results, employing a PCR-RFLP method, showed no difference in allele and genotype frequencies of the D3 BalI polymorphism (Ser9/Gly9) between Japanese alcoholics and controls. Moreover, these frequencies were not altered in alcoholics with inactive aldehyde dehydrogenase-2 (ALDH2), a well-defined negative risk factor for alcoholism. These results strongly suggest that the dopamine D3 receptor is not associated with alcoholism.

Adult↗
PubMed2001

Serotonin transporter gene polymorphism and psychiatric disorders in NF1 patients.

Neurofibromatosis type 1 (NF1) is an autosomal-dominant genetic disease characterized by a broad clinical expression. Comorbid affective disorders, anxiety disorders, and suicide are frequently observed during NF1. The promoter marker (5-HTTLPR) of the serotonin transporter gene (5-HTT) has been shown to be associated with major affective disorders, anxiety-related trait, and more recently with suicidal behavior. This gene is adjacent to the NF1 gene, raising the question of the implication of the 5-HTT gene in the psychiatric comorbidity during NF1. Eighty-eight patients with NF1 and 184 screened controls were typed for the 5-HTTLPR. No deviation from the Hardy-Weinberg equilibrium in patients was observed. In addition, allele and genotype frequencies were similar in the two groups. Our data do not support the implication of the 5-HTT gene in the psychiatric comorbidities of NF1.

Alleles↗