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Polymorphism Technique (polymorphism + technique)
Kinds of Polymorphism Technique Selected AbstractsA novel mutation in the PSEN1 gene (L286P) associated with familial early-onset dementia of Alzheimer type and lobar haematomasEUROPEAN JOURNAL OF NEUROLOGY, Issue 12 2007R. Sánchez-Valle The aim of this study was to describe a novel mutation in exon 8 of the presenilin gene (L286P) associated with early-onset autosomal dominant Alzheimer's disease (AD) and lobar haematomas. The proband was a woman who developed cognitive decline with predominant memory loss at the age of 35 years. The patient died at the age of 54 years and the neuropathological examination confirmed the diagnosis of AD. Three of her four siblings, one parent and one sibling of her parent had suffered from cognitive decline at ages between 35 and 42 years. Three of them also presented lobar haematomas. The neuropathological examination, available in one of them, disclosed the presence of severe amyloid angiopathy as the cause of the haematoma. The study of PSEN1 gene with single strand conformation polymorphism technique failed to show abnormalities suggestive of mutations. Direct sequencing disclosed the presence of a missense mutation in codon 286 (L286P) in the proband and her already affected descendent, which was absent in the healthy sibling. L286P is a novel mutation in PSEN1 that causes familial early-onset AD and brain haematomas related to amyloid angiopathy. [source] Lack of association between the G-2548A polymorphism of the leptin gene and psoriasis in a Turkish populationINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 12 2007Nurten Kara PhD Background,, Psoriasis is a multifactorial disease in which genetic and inflammatory factors play important roles. Leptin is classified as a cytokine and plays an important role in the regulation of the T-helper response. A common polymorphism in the promoter of the human leptin gene (G-2548A) may have a role in the pathogenesis of psoriasis. Aim, To investigate the association between psoriasis and leptin gene polymorphism (G-2548A). Methods, The study involved 109 patients with psoriasis and 125 healthy controls. Analyses of G-2548A polymorphism of the leptin gene were made by the polymerase chain reaction-restriction fragment length polymorphism technique. The genotypes (GG, GA, and AA of leptin gene G-2548A) and alleles (G and A) were scored and the frequencies were estimated. The frequencies of alleles and genotypes in patients and controls were compared. The relationship between leptin gene polymorphism and the clinical features of the patients was analyzed. Results, Both genotype [odds ratio (OR), 0.921; 95% confidence interval (CI), 0.501,1.694; P = 0.792] and allele (OR, 0.864; 95% CI, 0.600,1.242; P = 0.429) frequencies were not significantly different between patient and control groups. In addition, there was no significant association between genotype and allele frequencies and the clinical characteristics of psoriasis. Conclusion, In this case,control study, no evidence of association between the G-2548A variant of the leptin gene and psoriasis was found. [source] HSP70-hom gene single nucleotide (+2763 G/A and +2437 C/T) polymorphisms in sarcoidosisINTERNATIONAL JOURNAL OF IMMUNOGENETICS, Issue 2 2006K. Bogunia-Kubik Summary In the present study, two coding polymorphisms within the heat shock protein 70-hom gene (HSP70-hom) were analysed. One hundred and thirty-eight individuals were studied, including 42 Polish patients with sarcoidosis, 13 of which presented with Löfgren's syndrome (LS), and 94 control subjects. Dimorphisms at positions +2763 (A/G) and +2437 (C/T) of the HSP70-hom gene were typed using amplification refractory mutation system and polymerase chain reaction,restriction fragment length polymorphism technique, respectively. A significant prevalence of the HSP(+2437)-C allele and the HSP(+2437)-CC homozygous genotype was observed in patients with sarcoidosis and in those presenting with LS as compared to controls (P < 0.001 in all comparisons made). A majority of HLA-DRB1*03-positive patients with LS were carrying both HSP(+2437)-C and (+2763)-G alleles, and the concomitant presence of these three genetic factors was more frequent among patients with LS as compared to patients without LS (0.54 vs. 0.17, P < 0.05) and controls (0.54 vs. 0.01, P < 0.001). The association of the HSP(+2437)-C allele with sarcoidosis and LS appeared to be independent of the presence of DRB1*03, although this HLA specificity was associated with LS manifestation. The HSP(+2763)-G allele was independently associated with neither sarcoidosis nor LS. However, this HSP(+2763)-G allele was present with either DRB1*03 or HSP(+2437)-C within the same haplotypes in the patients and this might explain the observed prevalence of DRB1*03, HSP(+2437)-C and (+2763)-G in patients with LS. In conclusion, HSP(+2437)-C allele was found as a factor associating with susceptibility to sarcoidosis and LS. [source] Effect of wine yeast monoculture practice on the biodiversity of non- Saccharomyces yeastsJOURNAL OF APPLIED MICROBIOLOGY, Issue 1 2004M.A. Ganga Abstract Aims:, The objective of this work was to study the effect of the use of Saccharomyces cerevisiae monocultures over the biodiversity of non- Saccharomyces yeasts in wine-producing areas in Chile. Methods and Results:, Microvinifications were carried out with grape musts of two areas. In one of them, the fermentation is carried out mainly in a spontaneous manner, whereas in the other the musts are inoculated with commercial yeasts. The isolated yeasts were identified by the internal transcribed (ITS)/restriction fragment length polymorphism technique. In the industrial production area less variability of yeast genera was observed as compared with the traditional area, an observation that is greatest at the end of the fermentation. Furthermore, a study of the production of extracellular enzymes was done. The majority of the yeasts showed at least one of the activities assayed with the exception of , -glycosidase. Conclusion:, The results suggest that in the industrialized area the diversity of yeasts is less in the traditional area. Likewise, the potentiality of the non- Saccharomyces yeasts as enzyme producers with industrial interest has been confirmed. Significance and Impact of the Study:, This study shows the negative effect of the use of monocultures over the biodiversity of yeasts in wine-producing regions. [source] Genetic and morphometric differentiation among island populations of two Norops lizards (Reptilia: Sauria: Polychrotidae) on independently colonized islands of the Islas de Bahia (Honduras)JOURNAL OF BIOGEOGRAPHY, Issue 7 2007C. F. C. Klütsch Abstract Aim, Anole lizards (Reptilia: Sauria: Polychrotidae) display remarkable morphological and genetic differentiation between island populations. Morphological differences between islands are probably due to both adaptive (e.g. differential resource exploitation and intra- or interspecific competition) and non-adaptive differentiation in allopatry. Anoles are well known for their extreme diversity and rapid adaptive speciation on islands. The main aim of this study was to use tests of morphological and genetic differentiation to investigate the population structure and colonization history of islands of the Islas de Bahia, off the coast of Honduras. Location, Five populations of Norops bicaorum and Norops lemurinus were sampled, four from islands of the Islas de Bahia and one from the mainland of Honduras. Methods, Body size and weight differentiation were measured in order to test for significant differences between sexes and populations. In addition, individuals were genotyped using the amplified fragment length polymorphism technique. Bayesian model-based and assignment/exclusion methods were used to study genetic differentiation between island and mainland populations and to test colonization hypotheses. Results, Assignment tests suggested migration from the mainland to the Cayos Cochinos, and from there independently to both Utila and Roatán, whereas migration between Utila and Roatán was lacking. Migration from the mainland to Utila was inferred, but was much less frequent. Morphologically, individuals from Utila appeared to be significantly different in comparison with all other localities. Significant differentiation between males of Roatán and the mainland was found in body size, whereas no significant difference was detected between the mainland and the Cayos Cochinos. Main conclusions, Significant genetic and morphological differentiation was found among populations. A stepping-stone model for colonization, in combination with an independent migration to Utila and Roatán, was suggested by assignment tests and was compatible with the observed morphological differentiation. [source] Molecular analysis of the thiopurine S-methyltransferase alleles in Bolivians and TibetansJOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 5 2005H.-F. Lu MT Summary Background:, Thiopurine drugs are used as immunosuppressant or cytotoxic drugs. Thiopurine S-methyltransferase (TPMT) methylates and thereby modulates the therapeutic and toxic effects of these drugs. The activity of TPMT is affected by genetic polymorphism of TPMT alleles, and these alleles have not been studied in Tibetans and Bolivians. Objectives:, To analyse the TPMT allelic frequencies in Tibetans and Bolivians. Methods:, We developed an inexpensive method for collecting blood and extracting genomic DNA. Genomic DNA was extracted from blood spots of 50 Tibetans and 115 Bolivians. The frequencies of allelic variants of TPMT gene (TPMT*1 to TPMT*8) were determined using polymerase chain reaction-restriction fragment length polymorphism technique. Results:, The allelic frequencies of TPMT*1 were 99 and 93·48% for Tibetans and Bolivians, respectively. The corresponding allelic frequencies of TPMT*3A were 0 and 6·52% and those of TPMT*3C were 1·0 and 0%. No TPMT*2, 3B, 3D, 4,8 were found in these two populations. Conclusions:, As with Caucasian populations, TPMT*3A is the most prevalent mutant allele in Bolivians. Our results may be of value in helping to guide the prescription of thiopurine drugs in these populations. [source] Lack of association between leptin G2548A gene polymorphism and Behçet's diseaseJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 1 2007F Aydin Abstract Background, Behçet's disease is a chronic, multisystem, inflammatory disease characterized by the predominance of T-helper 1 cytokines. The disease is also characterized by infiltration of lymphocytes and neutrophils into the affected tissues. Because cytokines are involved in the regulation of lymphocyte and phagocyte functions, they may play an important role in the pathogenesis of Behçet's disease. Leptin, a member of the gp 130 family of cytokines, induces a strong T-helper 1 response and is regarded as a proinflammatory inducer. Recent studies have shown that serum leptin concentration was increased in patients with Behçet's disease and correlated with disease activity. Objectives, We aimed to investigate the role of G2548A polymorphism of leptin gene in patients with Behçet's disease and compare the results with healthy controls. Patients and methods, A total of 93 subjects with Behçet's disease and 125 healthy controls were included in this study. Analyses of G-2548A polymorphism of the LEP gene were performed using the PCR-restriction fragment length polymorphism technique. The genotypes (GG, GA, and AA of leptin G2548A) and alleles (G and A of leptin 2548) were scored and the frequency was estimated. The frequencies of the alleles and genotypes in patients and controls were compared. We analysed the correlation between leptin gene polymorphism and the clinical features of BD. Results, Both genotype and allele frequencies were not significantly different between controls and Behçet's disease patients [OR = 0.67, 95% CI (0.35,1.29), P = 0.197 and OR = 0.77, 95% CI (0.52,1.15), P = 0.184]. We did not find any significant relationship between leptin gene polymorphism and the clinical features of BD (P > 0.05). Conclusion, In the present case-control study, we found no evidence of an association between the G-2548A variant of the leptin gene and BD among Turks. Further studies are needed to investigate serum leptin level to explain the mechanisms behind the lack of association between leptin G2548A gene polymorphism and BD. [source] Polymorphism of the ITS-2 region of the ribosomal DNA of the Triatominae Rhodnius domesticus, R. pictipes, R. prolixus and R. staliMEDICAL AND VETERINARY ENTOMOLOGY, Issue 4 2006M. P. NAEGELE Abstract The polymerase chain reaction,restriction fragment length polymorphism technique (PCR,RFLP) was used to compare Rhodnius domesticus (Neiva & Pinto), R. pictipes (Stal), R. prolixus (Stal) and R. stali (Lent, Jurberg & Galvão) (Hemiptera: Reduviidae). The enzyme BstUI differentiated R. domesticus, R. pictipes and R. prolixus, and HhaI differentiated R. domesticus, R. pictipes and R. stali. With the fingerprinting analysis generated by these two enzymes, it was possible to clearly identify all four species in the study. [source] Characterization of single nucleotide polymorphism markers for the green sea turtle (Chelonia mydas)MOLECULAR ECOLOGY RESOURCES, Issue 3 2009SUZANNE E. RODEN Abstract We present data on 29 new single nucleotide polymorphism assays for the green sea turtle, Chelonia mydas. DNA extracts from 39 green turtles were used for two methods of single nucleotide polymorphism discovery. The first approach employed an amplified fragment length polymorphism technique. The second technique screened a microsatellite library. Allele-specific amplification assays were developed for high-throughput single nucleotide polymorphism genotyping and tested on two Pacific C. mydas nesting populations. Observed heterozygosities ranged from 0 to 0.95 for a Hawaiian population and from 0 to 0.85 for a Galapagos population. Each of the populations had one locus out of Hardy,Weinberg equilibrium, SSCM2b and SSCM5 for Hawaii and Galapagos, respectively. No loci showed significant genotypic linkage disequilibrium across an expanded set of four Pacific nesting populations. However, two loci, SSCM4 and SSCM10b showed linkage disequilibrium across three populations indicating possible association. [source] A high-throughput protocol for extracting high-purity genomic DNA from plants and animalsMOLECULAR ECOLOGY RESOURCES, Issue 4 2008R. WHITLOCK Abstract DNA extraction techniques that employ the reversible binding of DNA to silica via chaotropic salts can deliver high-quality genomic DNA from plant and animal tissues, while avoiding the use of toxic organic solvents. Existing techniques that use this method are either prohibitively expensive, or are applicable to only a restricted set of taxa. Here we describe a cost-effective DNA extraction technique suitable for a wide range of plant and animal taxa that yields microgram quantities of high-molecular-weight genomic DNA at a throughput of 192 samples per day. Our technique is particularly robust for tissue samples that are insoluble or are rapidly discoloured or oxidized in standard DNA extraction buffers. We demonstrate the quality of DNA extracted using this method by applying the amplified fragment length polymorphism technique to plant species. [source] Association of p53 polymorphism with ICSI/IVF failure and recurrent pregnancy lossAUSTRALIAN AND NEW ZEALAND JOURNAL OF OBSTETRICS AND GYNAECOLOGY, Issue 2 2009FIROUZABADI Razieh Dehghani Background: The p53 tumour suppressor gene is a well-known factor regulating apoptosis in a wide variety of cells. Alterations in the p53 gene are among the most common genetic changes in human cancers. Several polymorphisms of the p53 tumour suppressor gene have been associated with recurrent pregnancy loss (RPL). Aims: To evaluate the association of polymorphisms p53 codon 72 with the response to in vitro fertilisation (IVF) treatment and occurrence of repeated miscarriages. Methods: The homozygous and heterozygous genotypes and allelic frequencies of Arg and Pro p53 at codon 72 were identified by using polymerase chain reaction,restriction fragment length polymorphism technique in 70 infertile women with more than two IVF failures. Each comparison was made with 97 women experiencing RPL and 32 fertile women each with at least two healthy children as the control group. Results: The frequency of homozygous Pro/Pro genotypes was found significantly higher among the women with RPL than the other two groups (P = 0.041). Whereas, Arg/Arg genotype was significantly different in the recurrent implantation failure (RIF) group (P = 0.005). Conclusion: It is concluded that p53 codon 72 polymorphism may serve as a susceptible factor affecting the chances of RPL and RIF. [source] A single-nucleotide polymorphism in the XPG gene, and tumour stage, grade, and clinical course in patients with nonmuscle-invasive neoplasms of the urinary bladderBJU INTERNATIONAL, Issue 4 2006SHIGERU SAKANO OBJECTIVE To evaluate whether the single nucleotide polymorphism (SNP), Asp1104His (G3507C), in the XPG gene affects malignant phenotypes of nonmuscle-invasive urinary bladder neoplasms (NIBN), by investigating associations between the SNP and clinicopathological variables in patients with NIBN. PATIENTS AND METHODS The 233 patients constituted newly diagnosed cases of primary NIBN in the Stockholm area. The Asp1104His polymorphism in the XPG gene was genotyped using a polymerase chain reaction-restriction fragment length polymorphism technique. RESULTS The GC + CC genotypes were more frequent in stage pT1 tumours at initial diagnosis than pTa (odds ratio 1.9, 95% confidence interval 1.0,3.5, P = 0.048). The difference was larger in the young group (4.6, 1.9,11.8, P = 0.001). In the young group, the GC + CC genotypes were significantly more frequent in high-grade than in low-grade tumours (3.1, 1.5,6.8, P = 0.004) whereas in the older group the genotypes were less frequent in high-grade tumours (0.3, 0.1,0.7, P = 0.007). The XPG genotypes were not associated with tumour recurrence, stage progression or survival. CONCLUSION These results suggest that the SNP in the XPG gene might be related to tumour invasiveness in NIBN. [source] | |||||||||||||