Search results for " Polymorphism."
showing 10 items of 1006 documents
A population genetic study of the endangered plant speciesLimonium dufourii(Plumbaginaceae) based on amplified fragment length polymorphism (AFLP)
1999
Limonium dufourii (Plumbaginaceae) is a triploid species with obligate apomictic reproduction and is endemic to the East Mediterranean coast of Spain, where it is present in only six populations, most of which have a very low number of individuals. Genetic variation and population structure in this species was studied using amplified fragment length polymorphisms (AFLPs) as markers, using the same individuals as in a previous study with random amplified polymorphic DNA (RAPD). Three different primers provided 252 bands of which 51 were polymorphic among the 152 individuals analysed. Those polymorphic bands were able to define 65 different phenotypes, of which all but two were present in onl…
Phylogenetic relationships, evolutionary origin, taxonomic status, and genetic structure of the endangered local Lower Elbe river (Germany) endemic O…
2005
Abstract Oenanthe conioides is an endangered local endemic of the Lower Elbe river region in Germany where it is found in areas with freshwater tides. Internal transcribed spacer (ITS) and amplified fragment length polymorphism (AFLP) markers were used to investigate its phylogenetic relationships, evolutionary origin, taxonomic status, and genetic structure. Oe. conioides is most closely related to Oe. aquatica and Oe. fluviatilis, and cannot be distinguished from Oe. aquatica by ITS sequence variation. Oe. aquatica is found mainly in standing or slow-flowing freshwater habitats. The AFLP analysis indicated that Oe. conioides may constitute a monophyletic lineage nested within Oe. aquatica…
Study of the Evolutionary Relationships among Limonium Species (Plumbaginaceae) Using Nuclear and Cytoplasmic Molecular Markers
2000
The genus Limonium, due to the patchiness of the natural habitats of its species as well as the high frequency of hybridization and polyploidy and the possibility of reproduction by apomixis, provides an example of all the principal mechanisms of rapid speciation of plants. As an initial study of evolution in this genus, we have analyzed intra- and interspecific variability in 17 species from section Limonium, the largest in the genus, based on RFLPs of cpDNA and nuclear rDNA ITS sequences. In the cpDNA analysis, 21 restriction enzymes were used, resulting in 779 fragments, 490 of which were variable and 339 parsimony informative. L. furfuraceum exhibited two relatively divergent cpDNA hapl…
A comprehensive study of polymorphisms in the ABCB1, ABCC2, ABCG2, NR1I2 genes and lymphoma risk.
2011
Owing to their role in controlling the efflux of toxic compounds, transporters are central players in the process of detoxification and elimination of xenobiotics, which in turn is related to cancer risk. Among these transporters, ATP-binding cassette B1/multidrug resistance 1 (ABCB1/MDR1), ABCC2/multidrug resistance protein 2 (MRP2) and ABCG2/breast cancer resistance protein (BCRP) affect susceptibility to many hematopoietic malignancies. The maintenance of regulated expression of these transporters is governed through the activation of intracellular "xenosensors" like the nuclear receptor 1I2/pregnane X receptor (NR1I2/PXR). SNPs in genes encoding these regulators have also been implicate…
A functional variant of the serotonin transporter gene (SLC6A4) moderates impulsive choice in attention-deficit/hyperactivity disorder boys and sibli…
2011
Item does not contain fulltext BACKGROUND: Impulsive drive for immediate reward (IDIR) and delay aversion are dissociable elements of the preference for immediate over delayed rewards seen in attention-deficit/hyperactivity disorder (ADHD). We hypothesized that IDIR would be associated with dopamine regulating genes and delay aversion would be associated with serotonin-regulating genes. METHODS: Impulsive drive for immediate reward and delay aversion were measured in 459 male children and adolescents (328 ADHD and 131 unaffected siblings) with a laboratory choice task. The sample was genotyped for the 5HTT (SLC6A4) promoter serotonin-transporter-linked polymorphic region polymorphism and a …
hierGWAS
2017
Testing individual SNPs, as well as arbitrarily large groups of SNPs in GWA studies, using a joint model of all SNPs. The method controls the FWER, and provides an automatic, data-driven refinement of the SNP clusters to smaller groups or single markers.
Genotyping of Legionella pneumophila serogroup 1 strains isolated in Northern Sicily, Italy.
2008
During a three-year period, from April 2002 to May 2005, one hundred-forty-seven samples, taken from technical systems of water distribution at point of use, were repeatedly collected at six different sites in Northern Sicily and assayed for the presence of Legionella pneumophila serogroup 1 and serogroups 2 to 14. At the first samplings, the water distribution systems of all the sites were heavily contaminated, and disinfection treatments by the superheat and flush method were therefore performed. Treatments were always successful against L. pneumophila sg.1, but only in a few cases against all other serogroups. Eighty-six strains of L. pneumophila sg. 1, isolated from 26 of these samples,…
Molecular analysis of the catechol-degrading bacterial community in a coal wasteland heavily contaminated with PAHs
2010
International audience; A PCR-based molecular tool was developed to estimate the diversity of the catechol-degrading bacterial community in a coal wasteland heavily contaminated with PAHS. A degenerate primer pair specific to catA sequences was designed by multiple alignment of known sequences coding a key intermediate of the β-ketoadiapate pathway degrading catechol, namely catechol 1,2-dioxygenase. The specificity of this primer pair was assessed in 21 pure strains by PCR and sequencing. Comparison of the 16S rDNA and catA phylogenies revealed an absence of congruence between these two genes. The primer set was able to amplify catA sequences in DNA extracts from an industrial soil highly …
Evidence of Genomic Instability in Campylobacter jejuni Isolated from Poultry
1998
ABSTRACT Poultry isolates of Campylobacter jejuni derived from a survey of meat processing batches were genotyped by pulsed-field gel electrophoresis (PFGE) of chromosomal DNA to establish the clonal relationships between single-colony isolates. In the majority of batches studied, one or two genotype patterns predominated. However, in one batch (batch A), 21 single-colony isolates gave 14 different PFGE genotypes. The banding patterns obtained with Sma I were sufficiently different to distinguish between genotypes, although the patterns also produced many common bands. The question of whether these isolates represented different clones or had a common clonal ancestry was addressed by additi…
Genotypic characterization of Bradyrhizobium strains nodulating small Senegalese legumes by 16S-23S rRNA intergenic gene spacers and amplified fragme…
2000
ABSTRACT We examined the genotypic diversity of 64 Bradyrhizobium strains isolated from nodules from 27 native leguminous plant species in Senegal (West Africa) belonging to the genera Abrus , Alysicarpus , Bryaspis , Chamaecrista , Cassia , Crotalaria , Desmodium , Eriosema , Indigofera , Moghania , Rhynchosia , Sesbania , Tephrosia , and Zornia , which play an ecological role and have agronomic potential in arid regions. The strains were characterized by intergenic spacer (between 16S and 23S rRNA genes) PCR and restriction fragment length polymorphism (IGS PCR-RFLP) and amplified fragment length polymorphism (AFLP) fingerprinting analyses. Fifty-three reference strains of the different B…