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At least 811 records · Page 45Linked to original sources
PubMed1997

Influence of pepsinogen gene polymorphisms on serum pepsinogen.

We identified pepsinogen C (PGC) gene polymorphisms by means of PCR, which amplified DNA in the region within the intron between exons 7 and 8, and by 6% polyacrylamide gel electrophoresis. Six alleles were found in a Japanese population. The frequencies of these alleles in 408 unrelated Japanese individuals were 0.074, 0.026, 0.335, 0.237, 0.016 and 0.314, respectively. The serum pepsinogen II level significantly decreased in the order of the allele 6 homozygote, the allele 6 heterozygote and the other genotypes (chi 2 = 7.850, D.F. = 2, p = 0.020). These findings indicated that the genetic background of serum pepsinogen should be considered when screening for stomach cancer by this procedure.

Adolescent↗
PubMed1988

DX alpha gene polymorphism in Graves' disease.

An HLA-DX alpha gene polymorphism was analysed by Southern blotting in 49 British patients with Graves' disease and 61 control subjects. Two previously described allelic fragments of Taq I digested genomic DNA at 2.1 kb (U) and 1.9 kb (L) were found. The genotype frequencies for UU, UL and LL did not differ from the controls in Graves' disease, either for the whole groups or when subdivided into HLA-DR3-positive and -negative subjects. There was a significant association of the U allele with HLA-DR3 in both controls (P less than 0.05) and Graves' disease (P less than 0.025). The results indicate that DX alpha polymorphism is not primarily associated with Graves' disease. The findings differ from recent studies which showed that DX alpha polymorphisms may contribute to susceptibility in other DR3-associated autoimmune diseases.

Alleles↗
PubMed2005

Human cytomegalovirus UL144 gene polymorphisms in congenital infections.

The human cytomegalovirus (HCMV) UL144 gene is a tumor necrosis factor-like receptor with the potential to affect HCMV virulence. HCMV strains display genetic variability in the UL144 region, and the analysis of a potential link between UL144 gene polymorphisms and disease severity has scarcely been studied. However, a correlation between the UL144 genotype and congenital-disease outcome has been reported in one previous study, with the observation that all asymptomatic infants had a single UL144 genotype. In order to confirm or refute this finding, we determined the UL144 polymorphisms of HCMV strains recovered from the amniotic fluids of 38 infected fetuses and compared them to HCMV strains obtained from 30 viremic adult controls. The UL144 sequences were distributed among five genotypes (A, B, C, AC, and AB), as previously described. We observed similar percentages of the three major genotypes A (37%), B (33%), and C (27%) in our population. The UL144 genotype distributions were similar among the group of infected adults and the group of infected fetuses and among symptomatic and asymptomatic fetuses (P < 0.05). In our series, all five UL144 genotypes could be vertically transmitted from mothers to fetuses, and all could cause symptomatic congenital infection. We concluded that determination of UL144 polymorphisms in cases of congenital infection is not relevant, since it is unlikely to help predict the outcome of the infection.

Adult↗
PubMed1995

Lack of association between an interleukin-1 receptor antagonist gene polymorphism and systemic lupus erythematosus.

Non-MHC linked genes may contribute to genetic predisposition to the development of systemic lupus erythematosus. The possibility that cytokine genes may be involved was raised by the observation of increased frequency in expression of an uncommon allele of an interleukin-1 receptor antagonist gene polymorphism and SLE in a recent U.K. study. We have not been able to show any significant differences in expression of this allele in SLE patients as a whole or in any patient subgroups. Our results actually show a slight decrease in the expression of this allele in SLE patients compared with healthy controls and in SLE patients with malar rash compared with SLE patients without malar rash.

Alleles↗
PubMed2003

Combination of dopamine D2 receptor gene polymorphisms as a possible predictor of treatment-resistance to dopamine antagonists in schizophrenic patients.

Both the A1 allele carriers of TaqI A and Del allele noncarriers of -141C Ins/Del for dopamine D(2) receptor (DRD(2)) gene polymorphisms have been reported to have a lowered DRD(2) density. The present study aimed to examine whether the combinations of these two DRD(2) gene polymorphisms predict treatment response to antidopaminergic agents in schizophrenic patients. Subjects consisted of 49 acutely exacerbated schizophrenic inpatients treated with bromperidol (30 cases, mean dose+/-S.D.: 11.4+/-4.8 mg/day) or nemonapride (19 cases, 18 mg/day). Clinical symptoms were evaluated using Brief Psychiatric Rating Scale (BPRS) before and 3 weeks after the treatment. DRD(2) genotypes were determined using a polymerase chain reaction method. The A1 noncarriers with a Del allele showed poorer percentage improvement in anxiety-depression symptom after 3-week treatment (n=9, 7.3+/-42.9%) than A1 carriers without Del alleles (n=25, 62.4+/-38.0%) or A1 noncarriers without Del alleles (n=10, 65.4+/-29.2%). However, these preliminary results should be replicated in further research with a larger number of the subjects in each haplotype subgroup.

Adult↗
PubMed2006

An igf-I gene polymorphism modifies the risk of diabetic retinopathy.

The role of IGF-I in the pathogenesis of diabetic retinopathy is unclear. We studied, prospectively, the relationship between an IGF-I gene polymorphism, retinal vessel diameters, and incident diabetic retinopathy in subjects with impaired glucose tolerance (IGT) or type 2 diabetes. In all 5,505 participants of the population-based Rotterdam Study (775 with IGT, 394 with type 2 diabetes, and 4,336 control subjects), fundus color transparencies were taken at baseline (between 1990 and 1993) and at follow-up (from 1997 to 1999). The wild-type genotype (i.e., carriers of the 192- or 194-bp alleles) was present in 72.7% of the participants, while 27.3% were variant carriers. Variant carriers with IGT or type 2 diabetes appeared to have larger retinal arteriolar and venular diameters at baseline than individuals with the wild-type genotype, but these differences did not reach statistical significance. This trend was especially observed in subjects who developed retinopathy at follow-up. In variant carriers with IGT/diabetes, an increase (odds ratio 1.8 [95% CI 1.0-3.2]; P = 0.04) in the risk of retinopathy was observed compared with participants with the wild-type genotype. In conclusion, our findings suggest that this IGF-I gene polymorphism is associated with an increased risk of diabetic retinopathy.

Aged↗
PubMed1996

Angiotensin converting enzyme gene polymorphism and renal artery resistance in patients with insulin dependent diabetes mellitus.

The present study was carried out to elucidate whether renal hemodynamic changes are associated with angiotensin converting enzyme (ACE) gene polymorphism in patients with insulin dependent diabetes mellitus (IDDM). We studied 32 Japanese patients with IDDM (aged 15 +/- 3 years in mean +/- SD) without renal failure or retinopathy. Renal hemodynamics were examined by duplex Doppler sonography and arterial resistance index was calculated. ACE genotypes were determined by polymerase chain reaction amplification. Resistance index (RI) of arcuate arteries in IDDM patients with DD genotype was significantly elevated, being 0.64 +/- 0.04, 0.66 +/- 0.05, and 0.71 +/- 0.05 for II, ID and DD genotype groups, respectively (II vs. DD, p < 0.02). In patients with DD genotype with normoalbuminuria (n = 27), it was also significantly elevated in DD genotype patients (II vs. DD, p < 0.02). In addition, multiple regression analysis with a forward elimination procedure showed that only the ACE genotype was associated with RI of arcuate arteries (R2 = 0.24, p < 0.01) among the parameters of sex, age, IDDM duration, body mass index, HbA1c, plasma glucose levels, serum levels of total cholesterol and creatinine, urinary albumin excretion index, mean blood pressure and ACE genotype. The present study demonstrated that renal arterial resistance is elevated in IDDM patients with DD genotype. ACE gene polymorphism which could be linked to intrarenal circulatory disturbance may be associated with the initiation and progression of diabetic nephropathy.

Adolescent↗
PubMed2006

[Association between the canine monoamine oxidase B (MAOB) gene polymorphisms and behavior of puppies in open-field test].

Excitability, activity and exploration behavior of puppies in a novel open-field were tested in a total of 204 two-month-old German shepherd dog, labrador retriever or English springer spaniel puppies. The polymorphisms of monoamine oxidase B gene (MAOB) were detected by PCR-RFLP. Statistics analysis indicated that genotype and allele frequencies of the polymorphisms were significantly different among three breeds (P < 0.01). With GLM analysis of SAS software, association analysis was conducted between MAOB gene polymorphisms and locomotion and vocalization behavior parameters in the open-field test. The results showed that MAOB gene polymorphisms had a significant effect on walking time, squares crossed, lying time, the times of standing up against walls(P < 0.01 or P < 0.05) and were associated with the times of posture change (P=0.064). Walking time and squares crossed were higher in TT genotype puppies than those in TC and CC puppies (P < 0.05) and the times of posture change and standing up against walls were also higher than those in CC (P < 0.05). In addition, lying time in CC genotype puppies were higher than that in TT (P < 0.05). MAOB had a positive effect on walking time, lying time, squares crossed, the times of posture change, the times of standing up against walls in the three dog breeds that was highly statistically significant (P < 0.01 or P < 0.05). Our results imply that MAOB gene significantly affects the excitability, activity and exploration behavior of puppies in open-field test and TT genotype has favorable effects in these behavior traits.

Animals↗
PubMed1999

Insulin gene polymorphism and premature male pattern baldness in the general population.

Insulin is found in hair follicles and may play a role in the regulation of androgen metabolism and the hair growth cycle, which are relevant to the loss of scalp hair known as male pattern baldness. An excess of dihydrotestosterone on balding scalp indicates that the condition is androgen dependent. Premature male pattern baldness may be the male phenotype of familial polycystic ovary syndrome, a condition characterized by high levels of androgens and insulin that has been linked to insulin gene polymorphism. Therefore, we studied possible associations between relevant insulin gene polymorphisms and premature male pattern baldness in the general community. We examined the distribution of three dimorphic restriction fragment length polymorphisms: HphI, PstI and FokI in cases consisting of 56 men aged 18-30 years with significant baldness, and in 107 control men aged 50 years or more with no indication of baldness. No significant differences between cases and controls in allele, genotype or haplotype frequencies were identified. We conclude that, in the general population, the insulin gene is not associated with premature male pattern baldness.

Adolescent↗
PubMed2001

Gene polymorphisms of immunoregulatory cytokines and angiotensin-converting enzyme in Wegener's granulomatosis.

Wegener's granulomatosis is a granulomatous and vasculitic disease of unknown origin. Gene polymorphisms are known to affect phenotypes of numerous diseases. Polymorphisms within the angiotensin-converting enzyme (ACE), transforming growth factor-beta1 (TGF-beta1), and interleukin-10 (IL-10) genes are suspected to modify the course of granulomatous disorders. We examined whether the genotype frequencies of the named polymorphisms differ in Wegener's granulomatosis from those in healthy controls. Thirty-nine patients with Wegener's granulomatosis were genotyped for the deletion/insertion polymorphism in intron 16 of the ACE gene, a biallelic polymorphism in codon 25 of the TGF-beta1 gene and a biallelic polymorphism at position -1082 of the IL-10 gene and compared with healthy blood donors. For the ACE polymorphism no significant differences were detected neither in the allele frequencies nor in the genotype frequencies. For TGF-beta1 a trend to genotype CG was found. The most interesting result was the observed, significant shift to genotype AA of the IL-10 polymorphism in Wegener's granulomatosis. IL-10 and TGF-beta1, immunoregulatory cytokines capable of down-regulating T helper cell type 1 response, showed a significant shift or a trend, respectively towards genotypes associated with reduced cytokine release, leading to the hypothesis that different immunoregulatory cytokine patterns dependent on gene polymorphisms might be involved in the pathogenesis of Wegener's granulomatosis.

Adult↗
PubMed2005

Leukotriene-related gene polymorphisms in patients with aspirin-intolerant urticaria and aspirin-intolerant asthma: differing contributions of ALOX5 polymorphism in Korean population.

The pathogenesis of aspirin (acetylsalicylic acid, ASA)-intolerant urticaria (AIU) is still poorly understood but it has recently been suggested that it is associated with the overproduction of leukotriene (LT). This is supported by evidence that cyclooxygenase 2 inhibitor is given safely to patients with AIU. The present study was designed to investigate the role of genetic polymorphism of LT related genes in the pathogenesis of AIU via a case-control study. We screened single nucleotide polymorphisms (SNPs) in genes encoding enzymes involved in leukotriene synthesis in the Korean population with AIU (n = 101), ASA-intolerant asthma (AIA, n = 95) and normal healthy controls (n = 123). Genotype was determined by primer extension reactions using the SNapShot ddNTP primer extension kit. Among 8 SNPs of four LT related genes, the polymorphism of ALOX5 at positions of -1708 G > A showed significant difference in genotype frequency between AIU and AIA (p = 0.01). Furthermore, there were significant differences observed in the frequencies of two ALOX5 haplotypes between the AIU group and AIA group (p < 0.05). However, there were no differences in allele, genotype, or haplotype frequencies of ALOX5 between the AIU group and the normal control group. These results suggested that ALOX5 has a differing contribution in two major clinical pathogenesis related to ASA-sensitivity.

5-Lipoxygenase-Activating Proteins↗
PubMed1998

Study of the frequencies of CYP1A1 gene polymorphisms and glutathione S-transferase mu1 gene in primary breast cancers: an update with an additional 114 cases.

We studied the polymorphisms m1 (Msp1 restriction site) and m2 (codon Val substitution) of CYP1A1 gene and the copy number of glutathione S-transferase mu1 (GSTM1) gene on 487 DNA of breast cancer primary tumours from Caucasian group. Tumours of patients aged 55 years and under at diagnosis presented a great proportion of wild m1 (-/-) genotype; 83.6% vs. 69.5% (p < 0.0006), and a higher percentage of copy number of GSTM1 equal or under one copy; 65.2% vs. 53.4% (p < 0.011) for older patients m1 and m2 variants are closely linked (p < 0.0000). Tumour with a low copy number of GSTM1 is correlated with high histological grading (p < 0.01) and high Cathepsin D concentrations (p < 0.02). The combinations of different genotypes showed that association wild m1 (-/-) genotype and copy number of GSTM1 inferior or equal to one copy is correlated with an early onset of breast cancer primary tumour 44% vs. 6.4% for m1 (-/+) or (+/+) genotype and copy number of GSTM1 superior to one (p < 0.0000). The CYP1A1 gene wild form seems to be associated with early cancer development in Caucasian patients.

Adult↗
PubMed2004

[Association between serotonin 2C gene polymorphisms and attention deficit hyperactivity disorder comorbid or not comorbid with learning disorder].

OBJECTIVE: To investigate the relationship between two HTR2C gene polymorphisms, that is C-759T and G-697C polymorphisms, and attention deficit hyperactivity disorder (ADHD) comorbid or not comorbid learning disorder (LD). METHODS: Blood samples were taken from 189 trios with probands of ADHD comorbid LD (ADHD+LD) and 299 trios with probands of ADHD not comorbid LD (ADHD-LD). DNA was extracted and PCR was performed to amplify the fragments containing both C-759T and G-697C polymorphisms. Aci I was used to detect different alleles of the two polymorphisms. Allele- based and haplotype- based TDT analysis were used to test the association of the two polymorphisms of HTR2C gene and ADHD-LD and ADHD+LD. RESULTS: -759C(chi(2)=6.961, P=0.008), -697G(chi(2)=8.346, P=0.004), as well as -759C/-697G haplotype were over- transmitted(chi(2)=9.000, P=0.002 7), while haplotype -759T/-697C was under- transmitted(chi(2)=7.784, P=0.005 3) to probands with ADHD-LD. No biased transmission of any allele and haplotype were found in families with probands of ADHD+LD. CONCLUSION: ADHD-LD and ADHD+LD are different at the level of HTR2C gene polymrohisms of C-759T and G-697C. HTR2C is related to ADHD-LD, while not related to ADHD+LD.

Attention Deficit Disorder with Hyperactivity↗
PubMed2006

[Association between serotonin 1D gene polymorphisms and attention deficit hyperactivity disorder comorbid or not comorbid disruptive behavior disorder].

OBJECTIVE: To investigate the relationship between two HTR1D gene polymorphisms, that is 1350T > C and 1236A > G polymorphisms, and attention deficit hyperactivity disorder (ADHD) comorbid or not comorbid disruptive behavior disorder (DBD). METHODS: Blood samples were taken from 90 trios with probands of ADHD comrbid DBD and 182 trios with probands of ADHD not comorbid DBD. DNA was extracted. 1350T > C and 1236A > G were genotyped by restriction fragment length polymorphism analysis. Transmit/disequilibrium test and haplotype analysis were used to test the association of the two polymorphisms of HTR1D gene and ADHD comorbid or not comorbid disruptive behavior disorder (DBD) separately. RESULTS: 1350T allele(chi2 = 3.67, P = 0.055)and G/T haplotype(chi2 = 3.84, P = 0.050)were overtransmitted, while 1350C allele(chi2 = 3.67, P = 0.055) and G/C haplotype(chi2 = 5.22, P = 0.022)were undertransmitted to probands of ADHD with DBD. No biased transmission of any allele and haplotype was found in families with probands of ADHD without DBD. CONCLUSION: ADHD comorbid or not comorbid DBD are different at the level of HTR1D gene polymrohisms of 1350T > C and 1236A > G. The current results indicate that ADHD with DBD has more heritable backgrounds when compared with ADHD without DBD.

Adolescent↗
PubMed1999

The TT genotype of the methylenetetrahydrofolate reductase C677T gene polymorphism is associated with the extent of coronary atherosclerosis in patients at high risk for coronary artery disease.

BACKGROUND: There are conflicting results on the relationship of N5,N10-methylenetetrahydrofolate reductase C677T gene variation in coronary artery disease and myocardial infarction. METHODS AND RESULTS: We analysed this gene variation in 2453 male Caucasians whose coronary anatomy was defined by coronary angiography. In the total sample, the C677T gene polymorphism was not associated with the presence or the extent of coronary artery disease (defined by the degree of vessel disease or by the coronary heart disease score according to Gensini). However, after excluding individuals with low risk profiles, an association between the C677T TT genotype and the Gensini score was found. This observation applies only to individuals (i) with high glucose levels, (ii) with low apolipoprotein Al/apolipoprotein B ratios, (iii) with low apolipoprotein Al/apolipoprotein B ratios and high lipoprotein (a) levels and (iv) with low apolipoprotein Al/apolipoprotein B ratios and high glucose concentrations. In patients with high glucose levels, the paraoxonase 191 A/B gene variation presupposed whether differences in Gensini scores between C677T C allele carriers and TT homozygotes became apparent, since only in paraoxonase 191 AA homoxygotes, but not in paraoxonase 191 B allele carriers, did C677T TT homozygotes have clearly higher Gensini scores than C allele carriers (two-way interaction; P = 0.013). The MTHFR C677T gene polymorphism was not associated with non-fatal myocardial infarction. CONCLUSION: The present study extends previous observations by the finding that carriers of the N5,N10-methylenetetrahydrofolate reductase C677T TT genotype with various coronary high risk profiles had clearly higher coronary heart disease scores than individuals with at least one C677T C allele.

Adult↗
PubMed1997

Angiotensin-converting enzyme gene polymorphism and cardiovascular disease.

1. The crucial role played by the renin-angiotensin-aldosterone system in the cardiovascular system and the immense therapeutic potential of angiotensin-converting enzyme inhibitors and, more recently, angiotensin II receptor blocking agents, in both heart failure and post-myocardial infarction is becoming increasingly evident. Polymorphisms within the genes controlling this enzyme system are candidates for the elucidation of the pathogenesis of cardiovascular disease and this link is both intriguing and provocative. Recently, an association between a polymorphism of the angiotensin-converting enzyme gene and phenotypic expression of cardiovascular disease, namely myocardial infarction, was reported. Since then, several small case-controlled studies have confirmed an association with manifestations of ischaemic heart disease or various other cardiac end-points. However, in a large prospective study the angiotensin-converting enzyme gene conferred no appreciable risk. 2. Our aim was to review the evidence that links polymorphisms of the angiotensin-converting enzyme gene with cardiovascular disease. We searched the Medline database (1990-1997) using the key words myocardial infarction, ischaemic heart disease, angiotensin-converting enzyme and polymorphisms and performed a search of the reference citation of relevant articles. We selected clinical studies on cardiovascular disease related to the angiotensin-converting enzyme genotype. 3. Taken together, the available evidence supports the notion that the DD-angiotensin-converting enzyme genotype adversely influences specific cardiovascular diseases but appears to do so in specific geographical areas and in particular patient subgroups. It is not yet known whether it does this through an interaction with other genes or by as yet unexplained biochemical mechanisms. 4. We should regard the current data with the angiotensin-converting enzyme genotype as an intriguing clue in the pathogenesis of cardiovascular disease. However, the main factor against this potential benefit is that the impact of the DD genotype appears to be small and its clinical manifestations rather heterogeneous.

Cardiovascular Diseases↗
PubMed2001

Vitamin D receptor gene polymorphism is related to bone density, circulating osteocalcin, and parathyroid hormone in healthy adolescent girls.

Bone mineral density (BMD) in adolescence is under strong genetic control and may influence the risk of future osteoporosis and resulting fracture. We investigated the vitamin D receptor (VDR) gene polymorphisms ApaI, BsmI, FokI, and TaqI, in relation to BMD, circulating calcium, osteocalcin, and parathyroid hormone (PTH) concentrations in healthy Caucasian girls (n = 99; mean (+/- SD) age 16.9 +/- 1.2 years). BMD of the total body, femoral neck, and lumbar spine, and bone area of the femur, lumbar spine, and total body were measured using dual energy X-ray absorptiometry. BMD values were adjusted for age, body height, body weight, and physical activity. Using ANOVA, the ApaI genotype Aa had lower circulating levels of osteocalcin (P < 0.01), higher levels of PTH (P = 0.04), and there was a strong tendency toward a significantly higher lumbar spine BMD (P = 0.08) compared with aa subjects. BMD of the lumbar spine (P = 0.02), but not femoral neck or total body, was higher in Bb subjects compared with their bb counterparts. There was no difference in BMD at any measured site of the FokI alleles. There was a strong tendency for a higher BMD at the lumbar spine of Tt subjects compared with TT subjects (P = 0.05). Neither of the different VDR polymorphisms was related to BMD before adjustment for age, body weight, body height, and physical activity. In conclusion, VDR gene polymorphism, defined by ApaI, is related to differences in circulating osteocalcin and PTH, and BsmI is related to lumbar spine BMD in healthy adolescent girls. The results stress the importance of adjusting BMD for confounding factors, such as body weight and physical activity, in order to be able to find any genotype effect on BMD.

Adolescent↗
PubMed2006

Association analysis of delta-opioid receptor gene polymorphisms in methamphetamine dependence/psychosis.

The role of the delta-opioid receptor (OPRD1) in methamphetamine (MAP) addiction was investigated using association analysis between OPRD1 gene polymorphisms and MAP dependence/psychosis. DNA samples from Japanese patients with MAP dependence/psychosis were analyzed to find polymorphisms in OPRD1 gene exons and exon-intron boundaries. One novel single nucleotide polymorphism (SNP) in intron 1 and two SNPs in exon 3 were identified. The two SNPs in exon 3 were in linkage disequilibrium. No significant difference was observed in either genotypic or allelic frequencies of these SNPs between controls (n = 260) and MAP dependent/psychotic patients (n = 170). Global analyses using the three SNPs and subcategory analyses on clinical parameters also showed no significant differences. These results suggest that the OPRD1 gene variants may not be a factor in vulnerability to MAP dependence/psychosis.

Adult↗