Search results for "GENETIC VARIABILITY"
showing 10 items of 200 documents
Contribution of Taq polymerase-induced errors to the estimation of RNA virus diversity.
1998
The genetic diversity of a vesicular stomatitis virus population was analysed by RT-PCR, cloning and sequencing of two approximately 500 nucleotide regions of the virus genome. PCR amplifications were performed in parallel experiments with both Taq and Pfu DNA polymerases, and important differences were observed. Between 10 and 22 mutations were detected when virus populations were analysed by Taq amplification (20 clones from each region), whereas amplification of the same samples with Pfu revealed between 0 and 5 mutations. PCR fidelity assays, performed under the same PCR conditions as those used in the population analysis, showed that the Taq error-rate estimate of 0.27 x 10(-4) misinco…
Variability of the fimA gene in Porphyromonas gingivalis isolated from periodontitis and non-periodontitis patients
2011
Objective: The goal of this study was to determine the genetic variability of the fimA gene in Porphyromonas gingivalis isolates from Spanish patients. Study Design: Pooled subgingival samples were taken, processed and cultured in non-selective blood agar medium. Pure cultures of one to six isolates per patient were obtained and PCR and PCR-RFLP were used for fimbrillin gene (fimA) type determination of the extracted genomic (DNA). Results: Two hundred and twenty four Porphyromonas gingivalis isolates from 65 patients were analyzed consisting of 15 non-periodontitis patients (66 isolates) and 50 with periodontitis (158 isolates). Genotype II was the most prevalent (50.9%), while the other t…
GENETIC VARIABILITY AND DRIFT LOAD IN POPULATIONS OF AN AQUATIC SNAIL
2004
Population genetic theory predicts that in small populations, random genetic drift will fix and accumulate slightly deleterious mutations, resulting in reduced reproductive output. This genetic load due to random drift (i.e., drift load) can increase the extinction risk of small populations. We studied the relationship between genetic variability (indicator of past population size) and reproductive output in eight isolated, natural populations of the hermaphroditic snail Lymnaea stagnalis. In a common laboratory environment, snails from populations with the lowest genetic variability mature slower and have lower fecundity than snails from genetically more variable populations. This result s…
A family with various symptomatology suggestive of Anderson-Fabry disease and a genetic polymorphism of alpha galactosidase A gene.
2014
Background: Anderson/Fabry disease expresses a wide range of clinical variability in patients that it is possible to explain referring to a genetic variability with numerous mutations described in the literature (more than 600). Methods: We report some clinical cases of some members of a Sicilian family to express phenotypical variability of this disease in subjects with the same genetic mutation. Results: The first case was a 59-year-old female. Brain MRI revealed right frontal periventricular white matter of likely vascular-degenerative origin. The proband's alpha galactosidase A activity was 3.7. nmol/mL/h. Molecular genetics revealed a polymorphism: - 10 C. >. T; IVS 2-76_80del5; IVS…
Unequal distribution of RT-PCR artifacts along the E1-E2 region of Hepatitis C virus.
2009
Although viral variability studies have focused traditionally on consensus sequences, the relevance of molecular clone sequences for studying viral evolution at the intra-host level is being increasingly recognized. However, for this approach to be reliable, RT-PCR artifacts do not have to contribute excessively to the observed variability. Molecular clone sequences were obtained from an in vitro transcript to estimate the maximum error rate associated to RT-PCR for the Hepatitis C virus (HCV) E1-E2 region. On average, the frequency of RT-PCR errors was one order of magnitude lower than the level of intra-host genetic variability observed in samples from an HCV outbreak. However, RT-PCR err…
Pre-invasion history and demography shape the genetic variation in the insecticide resistance-related acetylcholinesterase 2 gene in the invasive Col…
2012
Abstract Background Invasive pest species offers a unique opportunity to study the effects of genetic architecture, demography and selection on patterns of genetic variability. Invasive Colorado potato beetle (Leptinotarsa decemlineata) populations have experienced a rapid range expansion and intense selection by insecticides. By comparing native and invasive beetle populations, we studied the origins of organophosphate (OP) resistance-associated mutations in the acetylcholinesterase 2 (AChE2) gene, and the role of selection and demography on its genetic variability. Results Analysis of three Mexican, two US and five European populations yielded a total of 49 haplotypes. Contrary to the exp…
Plant phenology and genetic variability in root and nodule development strongly influence genetic structuring of Rhizobium leguminosarum biovar vicia…
2008
Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699; International audience; The symbiotic relationships between legumes and their nitrogen (N-2)-fixing bacterial partners (rhizobia) vary in effectiveness to promote plant growth according to both bacterial and legume genotype. To assess the selective effect of host plant on its microsymbionts, the influence of the pea (Pisum sativum) genotype on the relative nodulation success of Rhizobium leguminosarum biovar viciae (Rlv) genotypes from the soil populations during plant development h…
Genetic Variability and Antigenic Diversity of Foot-and-Mouth Disease Virus
1990
Foot-and-mouth disease (FMD) is an acute systemic disease of cloven-hooved animals, including cattle, swine, sheep, and goats. Despite mortality rates being generally below 5%, FMD severely decreases livestock productivity and trade. It is considered the economically most important disease of farm animals. Near two thousand million doses of vaccine are used annually to try to control FMD, which, nevertheless, is enzootic in most South American and African countries, parts of Asia, the Middle East, and the south of Europe. The causative agent, foot-and-mouth disease virus (FMDV), is an aphthovirus of the family Picornaviridae, a historically important virus as it was the first recognized vir…
Genetic population structure of Epinephelus marginatus (Pisces, Serranidae) revealed by two molecular markers
2006
In this paper, data are presented regarding the population structure of dusky grouper (Epinephelus marginatus) which was sampled in the Mediterranean Sea and Atlantic Ocean using two different molecular markers, ND2 RFLP and cytochrome b (cyt b) sequence analysis. The main objective of the study is to analyse the genetic variability of E. marginatus in the Mediterranean Sea to define how the biological characteristics of the species, such as the dispersal capability of pelagic larvae and the benthonic-sedentary life style, can affect the genetic population structure or maintaining the gene flow or determining genetic differences. Furthermore, we considered an Atlantic sample to establish th…
Complete sequence, genotyping and comparative analysis of Pepino mosaic virus discovered isolates from Italy
2011
Pepino mosaic virus (PepMV) causes economic damage to the tomato industry worldwide. In Italy, the virus is endemic in Sicily, an important tomato-production region, and a new outbreak has been recorded in Sardinia after the first PepMV appearance in 2001. Italian PepMV isolates from these two geographically distant regions were molecularly characterized and the complete nucleotide sequence of four isolates was determined by walking primer strategy. The complete nucleotide and deduced amino acid sequences were analyzed and compared with published PepMV sequences. Italian isolates belong to the PepMV-Ch2 strain and had 97.2% to 98.5% identity with those of the reference PepMV-Ch2 deposited i…