Home About us Contact
|
Home About us Contact | ||
|
|
||
PCR Restriction Fragment Length Polymorphism (pcr + restriction_fragment_length_polymorphism)
Selected AbstractsThiopurine S -methyltransferase (TPMT) genetic polymorphisms in Mexican newbornsJOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 6 2009A. González-del Angel MD Abstract Background:, Thiopurine S -methyltransferase (TPMT) is involved in the toxicity and therapeutic efficacy of thiopurine drugs, and its gene exhibits genetic polymorphisms that differ across diverse populations. Four TPMT polymorphisms (TPMT*2, *3A, *3B and *3C) account for 80,95% of alleles that cause reduced enzyme activity. To date, only a single study in the Mexican population involving 108 individuals has been performed, but the regional and ethnic origin of this population was not described. Accordingly, information about the TPMT polymorphism in the Mexican population is limited. Objective:, To determine the TPMT allele and genotype frequencies in a sample of newborns from Mexico City. Methods:, Three hundred and sixty DNA samples from unrelated, anonymous individuals were obtained from dried blood spots collected on filter paper as part of the Newborn Screening National Program. Allele-specific polymerase chain reaction for the TPMT*2 allele and PCR restriction fragment length polymorphism for TPMT*3A, TPMT*3B, TPMT*3C alleles were used to determine the respective allelic and genotypic frequencies. Results and Discussion:, Of 720 TPMT alleles analysed, 49 (6·81%) were deficiency alleles. The most common deficiency allele was TPMT*3A (5·69%), followed by TPMT*3C (0·56%), TPMT*3B (0·28%) and TPMT*2 (0·28%). Fourty-five newborns were heterozygous for one mutant allele (12·5%) and two showed a genotype with two deficiency alleles (0·56%). Despite its unique ethnic composition, our Mexican population exhibited variant allele frequencies that were similar to some Caucasian populations. Conclusion:, Our data suggest that approximately 1 in 180 persons born in Mexico City might have low or undetectable TPMT enzyme activity, a frequency that, overall, is somewhat higher than that reported for Caucasian populations generally (1 in 300). [source] Matrix metalloproteinase-3 gene polymorphism in renal transplant patients with gingival overgrowthJOURNAL OF PERIODONTAL RESEARCH, Issue 1 2010A. Drozdzik Drozdzik A, Kurzawski M, Lener A, Kozak M, Banach J, Drozdzik M. Matrix metalloproteinase-3 gene polymorphism in renal transplant patients with gingival overgrowth. J Periodont Res 2009; doi: 10.1111/j.1600-0765.2009.01221.x. © 2009 The Authors. Journal compilation © 2009 Blackwell Munksgaard Background and Objective:, Gingival enlargement frequently occurs in transplant patients receiving immunosuppressive drugs. It was hypothesized that gingival enlargement associated with cyclosporine use results from reduced degradation of extracellular matrix in the gingiva. Matrix metalloproteinase-3 (MMP-3) is involved in biodegradation of the extracellular matrix, and its inhibition may contribute to an abnormal accumulation of fibronectin and proteoglycans, which are MMP-3 substrates. The aim of this study was to investigate whether an association exists between MMP-3 genotypes and gingival enlargement in kidney transplant patients medicated with cyclosporine A. Material and Methods:, Sixty-four unrelated kidney transplant patients suffering from gingival overgrowth, as well as 111 control transplant patients without gingival overgrowth, were enrolled in the study. Gingival overgrowth was assessed 6 mo after transplantation. During the post-transplant period all patients were given cyclosporine A as a principal immunosuppressive agent. MMP-3 polymorphism was determined using a PCR restriction fragment length polymorphism assay. Results:, In kidney transplant patients suffering from gingival overgrowth the mean gingival overgrowth score was 1.35 ± 0.57, whereas in control subjects the mean gingival overgrowth score was 0.0. The distribution of MMP-3 -1178A/*dupA alleles among all kidney transplant patients, as well as in the two study subgroups, did not differ significantly from Hardy,Weinberg equilibrium. The frequency of the MMP-3-1171*A/*A genotype (28.1% for gingival overgrowth vs. 26.1% for controls) and of the MMP-3-1171*dupA/*dupA genotype (32.8% for gingival overgrowth vs. 22.5% for controls) was similar for both study groups. The risk of gingival overgrowth was lowest among patients carrying the MMP-3-1171*A/*dupA genotype (odds ratio 0.52), but this did not differ markedly from the other genotypes. Conclusion:, No association between MMP-3 gene polymorphism and gingival overgrowth was revealed in kidney transplant patients administered cyclosporine A. [source] High mitochondrial differentiation levels between wild and domestic Bactrian camels: a basis for rapid detection of maternal hybridizationANIMAL GENETICS, Issue 3 2010K. Silbermayr Summary Hybridization between wild species and their domestic congeners often threatens the gene pool of the wild species. The last wild Bactrian camel (Camelus ferus) populations in Mongolia and China are examples of populations facing such a hybridization threat. To address this key issue in the conservation of wild camels, we analysed wild, hybrid and domestic Bactrian camels (Camelus bactrianus) originating from Mongolia, China and Austria. Through screening of an 804-base-pair mitochondrial fragment, we identified eight mitochondrial haplotypes and found high sequence divergence (1.9%) between C. ferus and C. bactrianus. On the basis of a mitochondrial DNA sequence fixed difference, we developed a diagnostic PCR restriction fragment length polymorphism (PCR-RFLP) assay to differentiate between wild and domestic camel samples. We applied the assay to 81 individuals and confirmed the origin of all samples including five hybrids with known maternal ancestry. The PCR-RFLP system was effective for both traditional (blood, skin) and non-invasive samples (faeces, hair), as well as for museum specimens. Our results demonstrate high levels of mitochondrial differentiation between wild and domestic Bactrian camels and that maternal hybridization can be detected by a rapid and reliable PCR-RFLP system. [source] Association between tumour necrosis factor gene polymorphisms and the clinical types of patients with chronic hepatitis B virus infectionCLINICAL MICROBIOLOGY AND INFECTION, Issue 1 2005X.-W. Xu Abstract A PCR restriction fragment length polymorphism assay was used to analyse single-nucleotide polymorphisms in the tumour necrosis factor (TNF)-, and TNF-, genes of 56 patients with chronic severe hepatitis B virus (HBV) infection, 71 patients who either had chronic mild HBV infection or who were asymptomatic carriers, and 90 healthy controls. The serum TNF-, concentrations in patients with chronic severe HBV infection were compared to those of 30 healthy controls by radioimmunoassay. The frequencies of the TNF1/2 genotype and the TNF2 allele were greater in patients with chronic severe HBV infection than in healthy controls (25% vs. 11.1%, p 0.015; 12.5% vs. 5.6%, p 0.036, respectively) and patients with chronic mild HBV infection and asymptomatic carriers (25% vs. 8.8%, p 0.011; 12.5% vs. 4.2%, p 0.015, respectively). Heterozygotes carrying the TNF2 allele had higher levels of serum TNF-, than homozygotes for the wild-type allele among all patients with chronic severe HBV infection (p < 0.01). The genotype distribution and allele frequency of TNF-, were similar for patients with chronic severe HBV infection and healthy controls, but the frequency of the TNF-,*2/2 genotype in patients with chronic mild HBV infection and asymptomatic controls was lower than for healthy controls (9.9% vs. 22.4%, p 0.043) or patients with chronic severe HBV infection (9.9% vs. 26.8%, p 0.043), although this was not significant after correction for multiple testing. It was concluded that TNF-, gene polymorphisms may play an important role as a host factor in the progression of HBV infection. [source] | ||||||||||