Allele-specific Primers (allele-specific + primer)

Distribution by Scientific Domains


Selected Abstracts


Study of V1a vasopressin receptor gene single nucleotide polymorphisms in platelet vasopressin responsiveness

JOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 3 2006
Kazi N. Hasan
Abstract There is a significant heterogeneity among individuals in terms of platelet aggregation response to arginine vasopressin (AVP). The aim of this study was to evaluate whether four single nucleotide polymorphisms (SNPs) in the promoter region of vasopressin V1a receptor gene (V1aR) could be used as genetic markers for divergent platelet aggregation response to AVP. Seventeen of 33 subjects showed more than 60% of maximum platelet aggregation and were classified as responders. Sixteen were classified as nonresponders because they had less than 30% aggregation. In a preliminary study, V1aR gene sequences were determined in two responders and two nonresponders. We found four SNPs in the promoter region of the V1aR gene: ,6951G/A, ,4112A/T, ,3860T/C, and ,242C/T. In all 33 subjects the genotypes of four SNPs were determined using either polymerase chain reaction (PCR) with allele-specific primers or PCR followed by restriction-fragment length polymorphism (RFLP). There were no differences in the AVP-induced aggregation between the subjects with and without variant alleles of each four SNPs. The genotype frequencies of four SNPs of V1aR were almost identical between AVP responders and nonresponders. These results suggest that the four SNPs in the promoter region of the V1aR gene may not be useful as genetic markers for platelet aggregation heterogeneity. J. Clin. Lab. Anal. 20:87,92, 2006. © 2006 Wiley-Liss, Inc. [source]


Prevalence of heparin-induced antibodies in patients with chronic renal failure undergoing hemodialysis

JOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 5 2005
Iván Palomo
Abstract Heparin-induced thrombocytopenia (HIT) type II is a serious complication of heparin therapy. It presents initially as thrombocytopenia, and is associated with thrombosis in 20,50% of the cases. HIT is related to the presence of heparin-induced antibodies (HIA), which show specificity for the PF4-heparin (PF4-H) complex. The Fc,RIIa receptor has been suggested to participate in the pathogenic mechanism of HIA. Since patients undergoing chronic hemodialysis (HD) are exposed repeatedly to heparin, we studied the prevalence of HIA and their eventual relationship with thrombocytopenia and/or thrombosis, and the possible participation of the Fc,RIIa polymorphism. We studied 207 patients with chronic renal failure (CRF) undergoing HD. As a control we included 130 blood donors and 28 patients with CRF without HD. The HIA patients were studied with the use of a PF4-H ELISA. Additionally, in some positive cases for the previous test, a 14C- serotonin release assay (14C-SRA) was performed. The polymorphism Fc,RIIa H/R131 was studied by polymerase chain reaction (PCR) with allele-specific primers. Thirty-seven patients (17.9%) undergoing HD presented with HIA. The majority of these antibodies were IgG, IgM, and IgA. The HIA investigated presented specificity against the PF4-H complex, but not against PF4 alone (P<0.001). Twelve out of 22 (54.5%) PF4-H antibodies were positive when tested with the 14C-SRA. The distribution of the Fc,RIIa polymorphism in patients and healthy controls was 42.6% and 41.6% for H/H131, 41% and 48.9% for the H/R131 isoform, and 16.4% and 9.5% for the R/R131 isoform, respectively. No statistically significant difference in the Fc,RIIa isoform distribution was found. Twenty-nine out of 156 patients (18.5%) presented thrombocytopenia, and 21/207 (12.4%) had thrombosis of the native vein arterio-venous fistula (AVF). We did not find any statistically significant between HIA and thrombocytopenia or thrombosis. An important proportion of patients with CRF undergoing HD developed HIA, but these cases were not associated with thrombocytopenia or thrombosis of AVF. The frequency of the Fc,RIIa polymorphism did not statistically differ between HIT type II and normal controls. J. Clin. Lab. Anal. 19:189,195, 2005. © 2005 Wiley-Liss, Inc. [source]


Comparative mapping of chicken anchor loci orthologous to genes on human chromosomes 1, 4 and 9

ANIMAL GENETICS, Issue 1 2001
S. P. Suchyta
Comparative mapping of chicken and human genomes is described, primarily of regions corresponding to human chromosomes 1, 4 and 9. Segments of chicken orthologues of selected human genes were amplified from parental DNA of the East Lansing backcross reference mapping population, and the two parental alleles were sequenced. In about 80% of the genes tested, sequence polymorphism was identified between reference population parental DNAs. The polymorphism was used to design allele-specific primers with which to genotype the backcross panel and place genes on the chicken linkage map. Thirty-seven genes were mapped which confirmed the surprisingly high level of conserved synteny between orthologous chicken and human genes. In several cases the order of genes in conserved syntenic groups differs between the two genomes, suggesting that there may have been more frequent intrachromosomal inversions as compared with interchromosomal translocations during the separate evolution of avian and mammalian genomes. [source]


The prognostic significance of HPV-16 genome status of the lymph nodes, the integration status and p53 genotype in HPV-16 positive cervical cancer: a long term follow up

BJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 2 2003
Zoltán Hernádi
Objective Prognostic evaluation of HPV-16 genome status of the pelvic lymph nodes, the integration status of HPV-16 and p53 codon 72 polymorphism in cervical cancer. Design Prospective cohort study. Setting Department of Gynaecological Oncology, University of Debrecen, Hungary. Sample Thirty-nine patients with HPV-16 positive cervical cancer. Methods Primary tumour specimens of 39 cervical cancer patients with HPV-16 positive primary tumour were subjected to multiplex polymerase chain reaction using HPV-16 E1/E2, E7 and p53 codon 72 allele-specific primers. Pelvic lymph nodes of the same patients were also tested for the presence of HPV-16 DNA and for its integration status using HPV-16 E7 and E1/E2 ORF specific primers, respectively. Main outcome measures Progression-free survival. Results Metastatic lymph nodes carried HPV-16 DNA more frequently than nodes with no evidence of disease (100.0% vs 35.7%, P= 0.001). Cases with HPV-16 positive nodes had higher recurrence rate than those with HPV-16 negative nodes (42.9% vs 11.1%, P= 0.009). There was no difference between cases with and without histologically proven nodal disease with regard to integration status of HPV-16 DNA in the primary tumour (integrated 90.9% vs 71.4%, episomal 9.1% vs 21.4%, mixed 0% vs 7.1%) and p53 codon 72 polymorphism (Arg/Arg 54.5% vs 67.9%, Pro/Pro 0 vs 7.1%, Arg/Pro 45.5% vs 21.4%). Conclusion Regardless of the presence of nodal metastasis, HPV-16 status of the nodes is a significant predictor of recurrent disease. HPV-16 integration status and p53 codon 72 genotype do not seem to have a bearing on disease outcome in cervical cancer with HPV-16 positive primary. [source]