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Tandem Repeat Polymorphism (tandem + repeat_polymorphism)
Selected AbstractsThe thymidylate synthase tandem repeat promoter polymorphism: A predictor for tumor-related survival in neoadjuvant treated locally advanced gastric cancerINTERNATIONAL JOURNAL OF CANCER, Issue 12 2006Katja Ott Abstract We evaluated DNA polymorphisms in the thymidylate synthase (TS) and 5,10- methylene-tetrahydrofolate reductase (MTHFR) genes for an association with response and survival in locally advanced gastric cancer treated with 5-FU based preoperative chemotherapy (CTx). DNA of 238 patients (CTx-group: total n = 135, completely resected (R0) n = 102; without CTx: R0 n = 103) was isolated from blood or from nontumorous tissues. In the CTx-group, genotyping of the tandem repeat and the G/C polymorphism in the triple repeat in the promoter region of the TS gene and of the C677T polymorphism of the MTHFR gene was performed. None of the TS or MTHFR genotypes were associated with histopathological response and only the TS tandem repeat polymorphism was significantly related to survival (all patients n = 135, p = 0.002; R0 resected patients n = 102, p = 0.007; log-rank test). Multivariate analysis revealed ypN (p < 0.001) and the TS tandem repeat polymorphism as independent prognostic factors in the CTx-R0-group (p = 0.003). Analyzing the prognostic significance of the TS polymorphisms in the R0-group without CTx, TS genotypes were not significantly associated with survival. Comparing survival between R0 patients with and without CTx in the respective TS genotype groups of the tandem repeat polymorphism, a significant survival benefit for the patients with CTx was found for the 2rpt/2rpt (n = 49; p = 0.002) and 2rpt/3rpt genotypes (n = 99; p = 0.004), but not for the 3rpt/3rpt genotype (n = 57; p = 0.93). Patients' survival after CTx was associated with the TS tandem repeat polymorphism. CTx did not improve survival of patients with the 3rpt/3rpt genotype. Thus, a different therapy might be more appropriate for these patients. © 2006 Wiley-Liss, Inc. [source] Association of serotonin transporter gene-linked polymorphic region and variable number of tandem repeat polymorphism of the serotonin transporter gene in lichen simplex chronicus patients with psychiatric statusINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 10 2008Necmettin Kirtak MD Background, The serotonin (5-hydroxytryptamine; 5-HT) is a key neurotransmitter in the central nervous system and a responsible mediator for the itch. Dysregulation of serotonergic pathways has been implicated in the pathogenesis of many complex neuropsychiatric diseases. Objectives, The purpose of this study was to evaluate the relationship between lichen simplex chronicus and dysfunction and serotonin transporter (5-HTT) gene polymorphism. Methods, Thirty-nine patients with lichen simplex chronicus and 61 healthy control subjects were examined. Results, The results for the patients and control subjects were not significantly different (P > 0.05) in long/long (L/L) and long/short (L/S) genotypes of 5-HTT gene-linked polymorphic region (HTTLPR) polymorphism, but short/short S/S genotype was lower in lichen simplex chronicus patients (17.9%) than in controls (42.6%). This difference was statistically significant (P = 0.028). The results for the patients and control subjects were not significantly different in 12/12, 10/12 and 10/10 genotypes of variable number of tandem repeat (VNTR) polymorphism (P > 0.05). Beck depression inventory (BDI) scores and symptom checklist-90-revised (SCL-90) psychotic subscale were overrepresented significantly in the 12/12 genotypes than 10/12 genotypes. State and Trait Anxiety Inventory tests (STAI-I and -II) point averages were not statistically significant (P > 0.05) Conclusion, S/S genotypes of HTTLPR polymorphism in the 5-HTT gene may be related to lichen simplex chronicus and that patients who have 12/12 genotypes of VNTR polymorphism may be affected psychiatrically. [source] Polymorphism in the Interleukin-1 Receptor Antagonist Gene Is Associated With Alcoholism in Spanish MenALCOHOLISM, Issue 10 2000Isabel J. Pastor Background: A polymorphism located in intron 2 of the interleukin-1 receptor antagonist (IL1RN) gene recently has been associated with the development of hepatic fibrosis in Japanese alcoholics. In the present study, we analyzed whether there is an association between this polymorphism, alcoholism, and alcoholic liver disease in a Spanish male population of alcoholics. Methods: The IL1RN genotype was assessed by polymerase chain reaction by using oligonucleotides that flank a variable nucleotide tandem repeat polymorphism located in intron 2 of this gene in 90 male alcoholic patients from Spain; 30 alcohol-dependent men, 30 alcohol abusers, and 30 alcoholics with liver cirrhosis. We also studied 40 healthy subjects. Results: The distribution of the IL1RN allelic frequencies in Spanish healthy subjects is similar to that previously reported in White subjects. However, the A1 allele is overrepresented in Spanish alcoholics when compared with healthy subjects. No significant differences in allelic frequencies were observed between alcoholics with liver cirrhosis and alcoholics without liver disease or between alcohol-dependent subjects and alcohol abusers. Conclusion: The presence of the A1 allele of the IL1RN gene is associated with a higher risk of alcoholism in Spanish men. [source] Inducible and endothelial constitutive nitric oxide synthase gene polymorphisms in Kawasaki diseasePEDIATRICS INTERNATIONAL, Issue 2 2003Vahid Khajoee AbstractBackground: Nitric oxide (NO) is secreted by immune and vascular endothelial cells, and appears to play important roles in the pathophysiology of Kawasaki disease (KD). Thus, genetic variations in NO synthase (NOS) genes may be involved in the development of coronary artery lesions (CAL) in KD. Methods: The present study investigated the association of endothelial constitutive NOS (ecNOS) and inducible NOS (iNOS) gene polymorphisms with the development of CAL in KD in a Japanese population. Results: The genotype distributions of 27-bp tandem repeat polymorphism within intron 4 of ecNOS gene did not show any significant difference between controls and KD patients with or without CAL. In addition, there was no significant association between whole-allele distribution of iNOS gene promoter (penta-repeat CCTTT) polymorphism and KD with or without CAL. Conclusion: These results did not support any association of ecNOS and iNOS gene polymorphisms to the development of CAL in KD patients in a Japanese population. [source] Association of polymorphisms in the dopamine D4 receptor gene and the activity-impulsivity endophenotype in dogsANIMAL GENETICS, Issue 6 2007K. Hejjas Summary A variable number of tandem repeats (VNTR) polymorphism in exon 3 of the human dopamine D4 receptor gene (DRD4) has been associated with attention deficit hyperactivity disorder (ADHD). Rodents possess no analogous repeat sequence, whereas a similar tandem repeat polymorphism of the DRD4 gene was identified in dogs, horses and chimpanzees. Here, we present a genetic association study of the DRD4 VNTR and the activity-impulsivity dimension of the recently validated dog-ADHD Rating Scale. To avoid false positives arising from population stratification, a single breed of dogs (German shepherd) was studied. Two DRD4 alleles (referred to as 2 and 3a) were detected in this breed, and genotype frequencies were in Hardy,Weinberg equilibrium. For modelling distinct environmental conditions, ,pet' and ,police' German shepherds were characterized. Police German shepherds possessing at least one 3a allele showed significantly higher scores in the activity-impulsivity dimension of the dog-ADHD Rating Scale than dogs without this allele (P = 0.0180). This difference was not significant in pet German shepherds. To the best of our knowledge, this is the first report of an association between a candidate gene and a behaviour trait in dogs, and it reinforces the functional role of DRD4 exon 3 polymorphism. [source] Serotonin Transporter Protein Polymorphism and Harm Avoidance Personality in Migraine without AuraHEADACHE, Issue 6 2006Jeong Wook Park MD Objective.,To investigate polymorphisms in the serotonin transporter protein gene and harm avoidance personality dimension in patients with migraine without aura (MWOA). Background.,The serotonin transporter protein is a key modulator of serotonergic synaptic neurotransmission. Two polymorphic regions of the gene for serotonin transporter protein have been found, and are associated with variations in the functional activity of serotonin caused by differing transcriptional efficiency. The harm avoidance (HA) personality trait may also be heritable and associated with altered serotonergic neurotransmitter activity. Design.,We amplified the polymorphism in the promoter of serotonin transporter protein (5-HTTLPR) and the variable number of tandem repeats polymorphism within intron 2 (VNTR) using the polymerase chain reaction and performed genotype polymorphism analyses in 97 patients with MWOA and 100 healthy controls. We investigated serotonin-related personality traits by evaluating the HA personality dimension using a tridimensional questionnaire. Results.,The genotype frequencies and allele distributions of 5-HTTLPR did not differ between patients with MWOA and controls. The VNTR genotype STin2.12/STin2.12 was significantly more common in patients with MWOA (90%) than in controls (77%; P= .017). Patients with MWOA also had HA scores (21.9 ± 6.4) significantly higher than those of controls (16.3 ± 6.1; P < .001). Conclusions.,Serotonergic activity might be involved in the development of MWOA and VNTR of serotonin transporter gene might be one of the genetically contributing factors. [source] A variable number of tandem repeats polymorphism influences the transcriptional activity of the neonatal Fc receptor ,-chain promoterIMMUNOLOGY, Issue 1 2006Ulrich J. H. Sachs Summary The neonatal Fc receptor, FcRn, plays a central role in immunoglobulin G (IgG) transport across placental barriers. Genetic variations of FcRn-dependent transport across the placenta may influence antibody-mediated pathologies of the fetus and the newborn. Sequencing analysis of 20 unrelated individuals demonstrated no missense mutation within the five exons of the FcRn gene. However, a variable number of tandem repeats (VNTR) region within the FcRn promoter was observed, consisting of five different alleles (VNTR1,VNTR5). Alleles with two (VNTR2) and three (VNTR3) repeats were found to be most common in Caucasians (7·5 and 92·0%, respectively). Real-time polymerase chain reaction revealed that monocytes from VNTR3 homozygous individuals express 1·66-fold more FcRn transcript than do monocytes from VNTR2/VNTR3 heterozygous individuals (P = 0·002). In reporter plasmid assays, the VNTR3 allele supported the transcription of a reporter gene twice as effectively as did the VNTR2 allele (P = 0·003). Finally, under acidic conditions, monocytes from VNTR3 homozygous individuals showed an increased binding to polyvalent human IgG when compared with monocytes from VNTR2/VNTR3 heterozygous individuals (P = 0·021). These data indicate that a VNTR promoter polymorphism influences the expression of the FcRn receptor, leading to different IgG-binding capacities. [source] No correlation of five gene polymorphisms with periodontal conditions in a Greek populationJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 11 2006D. Sakellari Abstract Background: Various studies have examined possible correlations between a number of cytokine gene polymorphisms and periodontal disease in populations of different origins. The present study sought the correlation between four single-nucleotide polymorphisms (IL1A+3954, IL1B+4845, TNFA,308, COL1A1 Sp1), a variable number of tandem repeats polymorphism (IL1RN intron 2) and periodontal conditions in subjects of Greek origin. Methods: One hundred and ninety-two healthy subjects, stratified as non-periodontitis and periodontitis (chronic and aggressive) cases, participated in the present study. Genotyping was performed by polymerase chain reaction-based techniques using the primers and conditions described in the literature. The frequencies of genotypes between study groups were compared using Genepop v3.3 genetic software and Instat statistical package. Results: No differences were observed among the groups concerning the distributions of genotypes under investigation. Conclusions: Carriage rates of the polymorphisms under investigation in systemically healthy subjects of Greek origin are well within the range reported for Caucasians but these polymorphisms cannot discriminate between non-periodontitis and periodontitis (chronic or aggressive) cases. [source] Variable number of tandem repeats polymorphism of platelet glycoprotein Ib , in Chinese people and CC genotype with aspirin sensitivity in patients with cerebral infarctionJOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 2 2009Y.-Y. Jin MM Summary Background and objective:, To study the prevalence of variable number of tandem repeats (VNTR) polymorphism in platelet membrane glycoprotein (GP) Ib , in a Chinese Han population and to determine the relationship between VNTR polymorphisms and aspirin resistance. Methods:, Three hundred healthy individuals and 110 patients with cerebral infarction volunteered to participate in this study. The genotype status of all participants was determined by polymerase chain reaction-restriction fragment length polymorphism analysis. Platelet aggregation in patients with cerebral infarction receiving aspirin (100 mg/day) for at least 7 days, was measured by optical transmission aggregometry. Results and discussion:, Only three alleles of GP Ib ,, namely, B, C and D, were found. Type A was not found in the Chinese Han participants. Aspirin-sensitive patients were significantly more often of CC genotype than aspirin-semi-responders. Conclusions:, Only three types of alleles B, C and D were detected in the north-eastern region of China. The CC genotype of the VTNR polymorphism in GPIb appears to be more sensitive to the inhibitory action of low-dose aspirin. [source] | ||||||||||