scholarly journals Genetic diversity and relatedness in aquaculture and marina populations of the invasive tunicate Didemnum vexillum in the British Isles

2021 ◽  
Author(s):  
M. B. Prentice ◽  
S. R. Vye ◽  
S. R. Jenkins ◽  
P. W. Shaw ◽  
J. E. Ironside
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Native Species ◽  
Didemnum Vexillum ◽  
Global Spread ◽  
History Of ◽  
Complex Life History ◽  
Source Populations ◽  
Successful Invader

AbstractIntroductions of invasive, non-native species in the marine environment are increasing as human activity within coastal areas rises. Genetic datasets are useful tools to identify source populations, track routes of invasions, and illuminate the role of genetic variation in the establishment and subsequent spread of novel introductions. Here, a microsatellite dataset is used to estimate the genetic diversity and population structure of 7 introduced Didemnum vexillum populations in Britain and Ireland, 4 of which are associated with aquaculture and 3 with marinas. Genetic differentiation observed between these populations indicates human-mediated transport as the main mechanism underlying the population structure of D. vexillum in Britain and Ireland. In addition to elucidating patterns of population structure we found that aquaculture sites showed significantly higher genetic diversity (measured as allelic richness) in comparison to the marina sites. We discuss these findings in relation to the history of each invasion, the complex life history of D. vexillum, and available evidence of the relative invasiveness of these populations. Our results show numerous interesting patterns which highlight further research avenues to elucidate the complex factors underlying the global spread of this successful invader.

scholarly journals POPULATION STRUCTURE OFDIPODOMYS INGENS(HETEROMYIDAE): THE ROLE OF SPATIAL HETEROGENEITY IN MAINTAINING GENETIC DIVERSITY

Evolution ◽  
1997 ◽  
Vol 51 (4) ◽  
pp. 1296-1310 ◽  
Author(s):  
Sara V. Good ◽  
Daniel F. Williams ◽  
Katherine Ralls ◽  
Robert C. Fleischer
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Spatial Heterogeneity

scholarly journals Phylogeography of hepatitis B: The role of Portugal in the early dissemination of HBV worldwide

2022 ◽  
Author(s):  
Rute Marcelino ◽  
Ifeanyi J Ezeonwumelu ◽  
Andre Janeiro ◽  
Paula Mimoso ◽  
Sonia Matos ◽  
...  
Keyword(s):  
Evolutionary Dynamics ◽  
Hbv Genotype ◽  
Hbv Genotypes ◽  
Molecular Clock Model ◽  
Global Spread ◽  
History Of ◽  
Spatio Temporal ◽  
Relaxed Molecular Clock ◽  
Nucleotide Substitution Model

In Portugal, the genetic diversity, origin of HBV, and the Portuguese role in the dissemination of HBV worldwide were never investigated. In this work, we studied the epidemic history and transmission dynamics of HBV genotypes that are endemic in Portugal. HBV pol gene was sequenced from 130 patients followed in Lisbon. HBV genotype A (HBV/A) was the most prevalent (n=54, 41.5%), followed by D [HBV/D; (n=44, 33.8%)], and E [HBV/E; (n=32, 24.6%)]. Spatio-temporal evolutionary dynamics was reconstructed in BEAST using a Bayesian Markov Chain Monte Carlo method, with a GTR nucleotide substitution model, an uncorrelated lognormal relaxed molecular clock model, a Bayesian skyline plot, and a continuous diffusion model. HBV/D4 was the first subgenotype to be introduced in Portugal around 1857 (HPD 95% 1699-1931) followed by HBV/D3 and A2 a few decades later. HBV/E and HBV/A1 were introduced in Portugal later, almost simultaneously. Our results also indicate a very important role of Portugal in the exportation of HBV/D4 and A2 to Brazil and Cape Verde, respectively, at the beginning of the XX century. This work clarifies the epidemiological history of HBV in Portugal and shows that Portugal had an important role in the global spread of this virus.

scholarly journals On genetic diversity in caraway: Genotyping of a large germplasm collection

PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0244666
Author(s):  
Daniel von Maydell ◽  
Heike Lehnert ◽  
Thomas Berner ◽  
Evelyn Klocke ◽  
Wolfram Junghanns ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Genome Size ◽  
Phylogenetic Trees ◽  
Germplasm Collection ◽  
Genotyping By Sequencing ◽  
Gene Pools ◽  
History Of ◽  
Winter Annual ◽  
Neighbor Network

Caraway (Carum carvi) is a widespread and frequently used spice and medicinal plant with a long history of cultivation. However, due to ongoing climatic changes, the cultivation is becoming increasingly risky. To secure caraway cultivation in future, timely breeding efforts to develop adapted material are necessary. Analysis of genetic diversity can accompany this process, for instance, by revealing untapped gene pools. Here, we analyzed 137 accessions using genotyping by sequencing (GBS). Hence, we can report a broad overview of population structure and genetic diversity of caraway. Population structure was determined using a principal coordinate analysis, a Bayesian clustering analysis, phylogenetic trees and a neighbor network based on 13,155 SNPs. Genotypic data indicate a clear separation of accessions into two subpopulations, which correlates with the flowering type (annual vs. biennial). Four winter-annual accessions were closer related to biennial accessions. In an analysis of molecular variance, genetic variation between the two subpopulations was 7.84%. In addition, we estimated the genome size for 35 accessions by flow cytometry. An average genome size of 4.282 pg/2C (± 0.0096 S.E.) was estimated. Therefore, we suggest a significantly smaller genome size than stated in literature.

scholarly journals Population Structure of Leishmania using POPSICLE reveals extensive dichotomy in zygosity and discloses the role of sex in diversity of the parasite

2018 ◽  
Author(s):  
Jahangheer S. Shaik
Keyword(s):  
Genetic Diversity ◽  
Population Genetics ◽  
Population Structure ◽  
Neurological Disorders ◽  
Mating Preference ◽  
F1 Hybrids ◽  
Driving Mechanisms ◽  
Multiple Cycles ◽  
Mosaic Aneuploidy

AbstractMosaic aneuploidy prevalent in organisms such as Leishmania and Fungi and in genomes of some neurological disorders and cancers manifest as non-integer haplotypes due to heterogeneity in somy across a population of cells. Thus, the tools designed for strictly haploid or diploid genomes are insufficient to study them. We addressed this issue by upgrading our population genetics tool POPSICLE for aneuploid genomes and studied the population structure of 50 strains of Leishmania to understand genetic diversity and the sexual strategies that predispose to that diversity. Leishmania showed enormous diversity but a dichotomic nature of extreme zygosities. To understand this dichotomy, we specifically studied two species, L. tropica that contained strains with both hetero and homozygosities and L. major that were mainly homozygous. The homozygosity in L. tropica was a consequence of extreme inbreeding while heterozygosity was due to recent hybridizations involving two different genotypes. In contrast, L. major also contained two different genotypes and products of extreme inbreeding but no recent hybridizations. The heterozygous strains of L. tropica that were geographically isolated from the homozygous strains were F1 hybrids that appeared sterile to each other while those in proximity to the homozygous strains were outcrosses involving multiple cycles of hybridization indicating their mating preference with homozygous strains. Development of POPSICLE for aneuploid genomes offers a unique tool for determining the shared ancestries and in reinforcing sex as one of the driving mechanisms for speciation as demonstrated for Leishmania. POPSICLE is a Java based utility available for free download at https://popsicle-admixture.sourceforge.io/

Population Structure of Dipodomys ingens (Heteromyidae): The Role of Spatial Heterogeneity in Maintaining Genetic Diversity

Evolution ◽  
1997 ◽  
Vol 51 (4) ◽  
pp. 1296 ◽  
Author(s):  
Sara V. Good ◽  
Daniel F. Williams ◽  
Katherine Ralls ◽  
Robert C. Fleischer
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Spatial Heterogeneity ◽  
Dipodomys Ingens
Sign in / Sign up

Export Citation Format

Share Document