Search results for "Variability"

Genetic similarity among Tunisian cultivated olive estimated through SSR markers

2013

Olive (Olea europaea L. subsp. europaea var. europaea) is one of the oldest fruit tree in the Mediterranean basin, and is cultivated for oil and canned fruit. Part of this interest is driven by the economic importance of olive oil which is increasing throughout the world due to its beneficial effect to human health. In Tunisia, olive has great socio-economic importance, with more than 60 millions olive trees cultivated for olive oil production including a wide range of cultivars which are widely extended from the north to the south regions of the country for its high economic value. Here, we applied microsatellites (SSRs) molecular markers to assess the genetic variability of the most impor…

Genetic Variability and Phylogenetic Relationships within Trypanosoma cruzi I Isolated in Colombia Based on Miniexon Gene Sequences

2010

Phylogenetic studies ofTrypanosoma cruzihave identified the existence of two groups:T. cruziI andT. cruziII. There are aspects that still remain unknown about the genetic variability within theT. cruziI group. Given its epidemiological importance, it is necessary to have a better understanding ofT. cruzitransmission cycles. Our purpose was to corroborate the existence of haplotypes within theT. cruziI group and to describe the genetic variability and phylogenetic relationships, based on single nucleotide polymorphisms (SNPs) found in the miniexon gene intergenic region, for the isolates from different hosts and epidemiological transmission cycles in Colombian regions. 31T. cruziisolates wer…

Defects in plant immunity modulate the rates and patterns of RNA virus evolution

2020

AbstractIt is assumed that host genetic variability for susceptibility to infection necessarily conditions virus evolution. Differences in host susceptibility can either drive the virus to diversify into strains that track different defense alleles (e.g., antigenic diversity) or to infect only the most susceptible genotypes. To clarify these processes and their effect on virulence, we have studied how variability in host defense responses determine the evolutionary fate of viruses. To accomplish this, we performed evolution experiments with Turnip mosaic potyvirus in Arabidopsis thaliana mutants. Mutant plants had disruptions in infection-response signaling pathways or in genes whose produc…

Chromosomal Dynamics in Cercopithecini Studied by Williams-Beuren probe mapping

2010

Chromosomal evolution in the tribe Cercopithecini and in related taxa is highly debated. Uncertainty in reconstruction is mainly related to the great genetic variability and polymorphism of the taxa. Recent molecular and karyological efforts individuate a split between genetically conservative, arbitrarily defi ned, “terrestrial” guenons and vervets, and genetically variable and derived “arboreal” guenons. We performed the mapping of WS loci probe (7q11.23) in order to verify the chromosomal dynamics of the genomes of three tree-dwelling species of the tribe: C. neglectus, C. mitis mitis, C. albogularis labiatus. Data from literature for the “ground-dwelling” Chlorocebus aethiops sabaeus ha…

Characterization of 10 trinucleotide microsatellite loci in the Critically Endangered Pyrenean yam Borderea chouardii (Dioscoreaceae)

2003

The low levels of allozymic variability found in the Critically Endangered Borderea chouardii prompted us to develop microsatellite markers to assess the genetic variability and population structure for the adequate conservation management of this species. A (CTT) n enriched partial genomic library was constructed. Ten polymorphic microsatellite loci were isolated from it, rendering 51 alleles in 47 individuals analysed. The allelic pattern observed for all of the loci with more than two alleles suggests that B. chouardii is tetraploid.

The genome-wide structure of two economically important indigenous Sicilian cattle breeds1

2014

Genomic technologies, such as high- throughput genotyping based on SNP arrays, provided background information concerning genome structure in domestic animals. The aim of this work was to inves- tigate the genetic structure, the genome-wide estimates of inbreeding, coancestry, effective population size (N e ), and the patterns of linkage disequilibrium (LD) in 2 eco- nomically important Sicilian local cattle breeds, Cinisara (CIN) and Modicana (MOD), using the Illumina Bovine SNP50K v2 BeadChip. To understand the genetic rela- tionship and to place both Sicilian breeds in a global context, genotypes from 134 other domesticated bovid breeds were used. Principal component analysis showed that…

RAPD variation within and among natural populations of outcrossing willow-leaved foxglove (Digitalis obscura L.)

1999

Random amplified polymorphic DNA (RAPD) markers were used to assess levels and patterns of genetic diversity in Digitalis obscura L. (Scrophulariaceae), an outcrossing cardenolide-producing medicinal plant species. A total of 50 plants from six natural populations on the Iberian Peninsula were analysed by six arbitrarily chosen decamer primers resulting in 96 highly reproducible RAPD bands. To avoid bias in parameter estimation, analyses of population genetic structure were restricted to bands (35 of 96) whose observed frequencies were less than 1–3/n in each population. The analysis of molecular variance (AMOVA) with distances among individuals corrected for the dominant nature of RAPDs (g…

2015

Small and isolated populations usually exhibit low levels of genetic variability, and thus, they are expected to have a lower capacity to adapt to changes in environmental conditions, such as exposure to pathogens and parasites. Comparing the genetic variability of selectively neutral versus functional loci allows one to assess the evolutionary history of populations and their future evolutionary potential. The genes of the major histocompatibility complex (MHC) control immune recognition of parasites, and their unusually high diversity is genes which is likely driven by parasite-mediated balancing selection. Here, we examined diversity and differentiation of neutral microsatellite loci and…

Genetic diversity and clonal variation within the main Sicilian olive cultivars based on morphological traits and microsatellite markers

2014

The richness of Olea europaea (L.) genetic resources in Sicily is well documented. In the last 30 years, mostof the local cultivars, landraces and ecotypes have been gathered together in a large ex-situ collection,containing more than 300 genotypes. In this study, 45 putative clones of the main Sicilian olive cultivarswere characterized morphologically using microsatellite markers to unambiguously identify possiblesuperior genotypes. The microsatellites employed were polymorphic (observed heterozygosity = 0.71;polymorphic information content = 0.59), discriminated 52% of the genotypes and enabled the detectionof intra-cultivar polymorphism, derived from both somatic mutations, indicating th…

Chimerism and genetic diversity within the cultivar group of pinots

2002

Three clones of Vitis vinifera cv. pinot gris were analysed at 50 microsatellite loci to assess the presence of intra-varietal genetic variability. Two clones revealed a polymorphism expressed by the presence of three alleles at 5 loci instead of the two expected for a diploid species. By sequencing the three alleles amplified at two loci, we confirm that they correspond to different allelic states of the same locus but differ in their number of repeat units. Such tri-allelic profiles could reveal periclinal chimeras in which the two cell layers of the apical meristem are genetically different. For two clones, this periclinal chimeric state has been deduced from the comparison of the genoty…