scholarly journals Genetic variation in lowland and mountain populations of Tofieldia calyculata and their ability to survive within low levels of genetic diversity

2021 ◽  
Author(s):  
Tomáš Vlasta ◽  
Zuzana Műnzbergová
Keyword(s):  
Genetic Diversity ◽  
Suitable Habitat ◽  
Herbarium Specimens ◽  
The Past ◽  
Low Genetic Diversity ◽  
Genetic Diversity And Structure ◽  
Population Sizes ◽  
Range Periphery ◽  
Low Levels ◽  
European Mountains

Abstract Loss of genetic diversity is expected to be a common reason for decline of populations of many rare species. To what extent this is true for populations at the range periphery remains to be explored. Alpine species with peripheral lowland populations are ideal but poorly known model system to address this issue. We investigated genetic diversity and structure of populations of Tofieldia calyculata, species common in central European mountains but highly endangered in lowlands using 17 microsatellite loci. We showed that lowland populations have lower genetic diversity than mountain populations and they are not clearly differentiated from mountain populations. Species probably survived the last glaciation in refugia in margins of Alps and western Carpathians. Some lowland populations are probably relict as well and contain unique genetic information. Their low genetic diversity is likely the result the of reduction of population sizes, gene flow during the Holocene and selfing. However postglacial colonization is also a case of some lowland populations. Based on data from herbarium specimens from extinct lowland populations, we demonstrated that lowland populations had low genetic diversity also in the past and main part of the genetic diversity was lost due to extinction of whole populations. Within population genetic diversity has not changed since the last century suggesting that these populations are able to survive with low levels of genetic diversity under suitable habitat conditions. This idea is also supported by finding of large viable recent populations with very low genetic diversity. We conclude that lowland populations are unique and deserve adequate conservation.

scholarly journals Microsatellite analysis of genetic diversity and structure of Bruguiera gymnorrhiza and Kandelia obovate

2018 ◽  
Vol 52 ◽  
pp. 00027 ◽  
Author(s):  
Mohammad Basyuni ◽  
Shigeyuki Baba ◽  
Hirosuke Oku
Keyword(s):  
Genetic Diversity ◽  
Allelic Diversity ◽  
Geographic Range ◽  
Microsatellite Analysis ◽  
Bruguiera Gymnorrhiza ◽  
Low Genetic Diversity ◽  
Genetic Diversity And Structure ◽  
Low Levels ◽  
High Level ◽  
F Statistics

Microsatellite loci were used for estimating genetic diversity and structure for three populations of B. gymnorrhiza and K. obovata (Rhizophoracea) in Okinawa, Japan. Thirty propagules of individual samples representing the population of both species were genotyped at five microsatellites. The level of observed heterozygosity (HO) was observed for several population, overall loci, ranged 0.422-0.800 with an average 0.627 for B. gymnorrhiza and 0.477-0.822 with an average 0.665 for K. obovata, indicating both species had relatively low genetic diversity. Both species showed low levels of allelic diversity, 3-5 and 3-5 alleles per locus, respectively. Gene diversitywas also maintained within populations (HS: 0.741 and 0.954). Additionally, an analysis of molecular variance (AMOVA) based on the immeasurable alleles model (F-statistics), for B. gymnorrhiza and K. obovata found that most of the variation resided within individuals in the total populations, i.e. 79.78 % and 69.90 % respectively, and among individuals within populations, i.e.14.30 % and 27.95 % respectively. There was little variation between populations, i.e. 5.92 % and 2.15 % for B. gymnorrhiza and K. obovata, respectively. The high-level genetic differentiation within individuals and populations both species may be due to the geographic range of the species, mating system, and environmental factors.

scholarly journals Genetic diversity of rice stem borer (Chilo suppressalis Walker) from Northern Iran and comparison with other countries

2016 ◽  
Vol 48 (3) ◽  
pp. 360 ◽  
Author(s):  
M. Shayanmehr ◽  
E. Yoosefi-Lafooraki
Keyword(s):  
Genetic Diversity ◽  
Stem Borer ◽  
Chilo Suppressalis ◽  
Mazandaran Province ◽  
Northern Iran ◽  
Low Genetic Diversity ◽  
High Gene ◽  
Major Pest ◽  
Different Populations ◽  
Low Levels

Rice striped stem borer, <em>Chilo suppressalis</em> Walker (Lepidoptera: Crambidae) is considered the major pest of rice in Iran. Because of the serious damage on rice in Northern Iran, the present study was conducted to investigate genetic diversity within populations of <em>C. suppressalis</em>, from Mazandaran using a template of cytochrome oxidase I gene, 750 bps, (<em>COI</em>). Later the haplotypes from Iran were compared with those found in other countries. According to the results of this study, there is very low genetic diversity (two haplotypes) among different populations of this pest in populations of Northern Iran. The genetic similarity and low levels of genetic diversity of these populations suggest that the pest colonization occurred relatively recently and there is high gene flow between these populations of the province. In addition, haplotypes of Mazandaran province are different with those found in other countries. The similarity of Iranian population (Simorgh) with one population from China indicated that China might be the origin of <em>C. suppresalis</em>.

Weak genetic structuring suggests historically high genetic connectivity among recently fragmented urban populations of the scincid lizard, Ctenotus fallens

2015 ◽  
Vol 63 (4) ◽  
pp. 279 ◽  
Author(s):  
Josef Krawiec ◽  
Siegfried L. Krauss ◽  
Robert A. Davis ◽  
Peter B. S. Spencer
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
Large Population ◽  
Geographic Distance ◽  
Genetic Erosion ◽  
Genetic Connectivity ◽  
Genetic Structuring ◽  
Low Genetic Diversity ◽  
Population Sizes

Populations in fragmented urban remnants may be at risk of genetic erosion as a result of reduced gene flow and elevated levels of inbreeding. This may have serious genetic implications for the long-term viability of remnant populations, in addition to the more immediate pressures caused by urbanisation. The population genetic structure of the generalist skink Ctenotus fallens was examined using nine microsatellite markers within and among natural vegetation remnants within a highly fragmented urban matrix in the Perth metropolitan area in Western Australia. These data were compared with samples from a large unfragmented site on the edge of the urban area. Overall, estimates of genetic diversity and inbreeding within all populations were similar and low. Weak genetic differentiation, and a significant association between geographic and genetic distance, suggests historically strong genetic connectivity that decreases with geographic distance. Due to recent fragmentation, and genetic inertia associated with low genetic diversity and large population sizes, it is not possible from these data to infer current genetic connectivity levels. However, the historically high levels of gene flow that our data suggest indicate that a reduction in contemporary connectivity due to fragmentation in C. fallens is likely to result in negative genetic consequences in the longer term.

scholarly journals Unusually Low Levels of Genetic Variation among Giardia lamblia Isolates

2007 ◽  
Vol 6 (8) ◽  
pp. 1421-1430 ◽  
Author(s):  
Smilja Teodorovic ◽  
John M. Braverman ◽  
Heidi G. Elmendorf
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Giardia Lamblia ◽  
Diarrheal Disease ◽  
Regulation Of Gene Expression ◽  
Genetic Exchange ◽  
Disease Etiology ◽  
Noncoding Regions ◽  
Low Genetic Diversity ◽  
Low Levels

ABSTRACT Giardia lamblia, an intestinal pathogen of mammals, including humans, is a significant cause of diarrheal disease around the world. Additionally, the parasite is found on a lineage which separated early from the main branch in eukaryotic evolution. The extent of genetic diversity among G. lamblia isolates is insufficiently understood, but this knowledge is a prerequisite to better understand the role of parasite variation in disease etiology and to examine the evolution of mechanisms of genetic exchange among eukaryotes. Intraisolate genetic variation in G. lamblia has never been estimated, and previous studies on interisolate genetic variation have included a limited sample of loci. Here we report a population genetics study of intra- and interisolate genetic diversity based on six coding and four noncoding regions from nine G. lamblia isolates. Our results indicate exceedingly low levels of genetic variation in two out of three G. lamblia groups that infect humans; this variation is sufficient to allow identification of isolate-specific markers. Low genetic diversity at both coding and noncoding regions, with an overall bias towards synonymous substitutions, was discovered. Surprisingly, we found a dichotomous haplotype structure in the third, more variable G. lamblia group, represented by a haplotype shared with one of the homogenous groups and an additional group-specific haplotype. We propose that the distinct patterns of genetic-variation distribution among lineages are a consequence of the presence of genetic exchange. More broadly, our findings have implications for the regulation of gene expression, as well as the mode of reproduction in the parasite.

Low genetic diversity and small long-term population sizes in the spring endemic watercress darter, Etheostoma nuchale

2010 ◽  
Vol 11 (6) ◽  
pp. 2267-2279 ◽  
Author(s):  
Brook L. Fluker ◽  
Bernard R. Kuhajda ◽  
Nicholas J. Lang ◽  
Phillip M. Harris
Keyword(s):  
Genetic Diversity ◽  
Low Genetic Diversity ◽  
Population Sizes

scholarly journals New data on the genetic diversity of European bison Bison bonasus (Linnaeus, 1758) in Belarus

2020 ◽  
Vol 2020 (19) ◽  
pp. 45-53
Author(s):  
Kanstantsin V. Homel ◽  
◽  
K. Śliwińska ◽  
Arseni A. Valnisty ◽  
Mikhail E. Nikiforov ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
National Park ◽  
Bison Bison ◽  
Fixation Index ◽  
European Bison ◽  
Bison Bonasus ◽  
Genetic Structuring ◽  
The Past ◽  
Low Genetic Diversity ◽  
Expected Heterozygosity

The paper presents data on the assessment of the genetic diversity of five subpopulations of the European bison (Bison bonasus) in Belarus — from the National Park “Belovezhskaya Pushcha”, the National Park “Pripyatsky”, the Osipovichi district (Mogilev area), SEI “Berezinsky Biosphere Reserve” and the Grodno region. In general, the work includes 30 samples of muscle tissue from the collection of Gene bank of wild fauna in SSPA “SPC NAS of Belarus on Bioresources” (Minsk, Belarus). Microsatellites were used as markers to assess genetic diversity, structure, and search for signs of a sharp decline in the size of bison subpopulations in the past. A total of 11 microsatellite markers were used, recommended by the Food and Agriculture Organization of the United Nations for cattle research. The analysis of B. bonasus subpopulation from the NP “Pripyatsky” showed signs of passing through the genetic bottleneck. All studied subpopulations are characterized by a similarly low genetic diversity level in all analyzed indicators (mean number of alleles, allelic diversity, observed and expected heterozygosity). The expected heterozygosity (He) for the three subpopulations from the NP “Belovezhskaya Pushcha”, the NP “Pripyatsky” and from the Osipovichi district ranged from 0.37 to 0.39. For the studied subpopulations, the values of the fixation index were negative. The assessment of the presence of genetic structuring between the subpopulations of bison from the NP “Belovezhskaya Pushcha”, the NP “Pripyatsky” and from the Osipovichi district based on the values of such indexes as Fst and DJost which showed no signs of genetic differentiation, which is also confirmed by principal coordinates analysis (PCoA). The European bison conservation in Belarus has required tremendous efforts in the past. So far, even though the impressively large population size reached in Belarus, B. bonasus status still should not be considered as stable, which is closely linked to aspects of its overall low genetic diversity. Our research confirmed the low genetic variability of Belarusian subpopulations. Therefore, the more extensive research concentrated on identifying genetic diversity is necessary to ensure the beneficial control of gene flow and register a potential correlation of unfavorable gene variants with possible inbreeding depression. These attempts are required to lay the groundwork for the management and protection of the European bison in Belarus.

scholarly journals Invasion genomics uncover contrasting scenarios of genetic diversity in a widespread marine invader

2021 ◽  
Vol 118 (51) ◽  
pp. e2116211118
Author(s):  
Cornelia Jaspers ◽  
Moritz Ehrlich ◽  
José Martin Pujolar ◽  
Sven Künzel ◽  
Till Bayer ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Propagule Pressure ◽  
Invasion Success ◽  
Invasion Dynamics ◽  
The Past ◽  
Marine Invasive Species ◽  
Successful Establishment ◽  
Low Levels ◽  
International Conventions ◽  
Dominant Paradigm

Invasion rates have increased in the past 100 y irrespective of international conventions. What characterizes a successful invasion event? And how does genetic diversity translate into invasion success? Employing a whole-genome perspective using one of the most successful marine invasive species world-wide as a model, we resolve temporal invasion dynamics during independent invasion events in Eurasia. We reveal complex regionally independent invasion histories including cases of recurrent translocations, time-limited translocations, and stepping-stone range expansions with severe bottlenecks within the same species. Irrespective of these different invasion dynamics, which lead to contrasting patterns of genetic diversity, all nonindigenous populations are similarly successful. This illustrates that genetic diversity, per se, is not necessarily the driving force behind invasion success. Other factors such as propagule pressure and repeated introductions are an important contribution to facilitate successful invasions. This calls into question the dominant paradigm of the genetic paradox of invasions, i.e., the successful establishment of nonindigenous populations with low levels of genetic diversity.

scholarly journals Contrasting maternal and paternal genetic variation of hunter-gatherer groups in Thailand

2017 ◽  
Author(s):  
Wibhu Kutanan ◽  
Jatupol Kampuansai ◽  
Piya Changmai ◽  
Pavel Flegontov ◽  
Roland Schröeder ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Mt Dna ◽  
Mtdna Haplogroups ◽  
The Past ◽  
Low Genetic Diversity ◽  
Related Group ◽  
Recent Origin ◽  
Mtdna Diversity ◽  
Founder Event ◽  
Northeastern Thailand

ABSTRACTThe Maniq and Mlabri are the only recorded nomadic hunter-gatherer groups in Thailand. Here, we sequenced complete mitochondrial (mt) DNA genomes and ~2.364 Mbp of non- recombining Y chromosome (NRY) to learn more about the origins of these two enigmatic populations. Both groups exhibited low genetic diversity compared to other Thai populations, and contrasting patterns of mtDNA and NRY diversity: there was greater mtDNA diversity in the Maniq than in the Mlabri, while the converse was true for the NRY. We found basal uniparental lineages in the Maniq, namely mtDNA haplogroups M21a, R21 and M17a, and NRY haplogroup K. Overall, the Maniq are genetically similar to other negrito groups in Southeast Asia. By contrast, the Mlabri haplogroups (B5a1b1 for mtDNA and O1b1a1a1b and O1b1a1a1b1a1 for the NRY) are common lineages in Southeast Asian non-negrito groups, and overall the Mlabri are genetically similar to their linguistic relatives (Htin and Khmu) and other groups from northeastern Thailand. In agreement with previous studies of the Mlabri, our results indicate that the Malbri do not directly descend from the indigenous negritos. Instead, they likely have a recent origin (within the past 1,000 years) by an extreme founder event (involving just one maternal and two paternal lineages) from an agricultural group, most likely the Htin or a closely- related group.

scholarly journals Classification of Genus Acanthopanax in Korea and Genetic Diversity Using Allozymes

2005 ◽  
Vol 54 (1-6) ◽  
pp. 206-210 ◽  
Author(s):  
M. K. Huh ◽  
H. W. Huh
Keyword(s):  
Genetic Diversity ◽  
Representative Sample ◽  
Genetic Relationships ◽  
Woody Species ◽  
Small Population ◽  
Geographic Ranges ◽  
Low Level ◽  
Low Genetic Diversity ◽  
Population Sizes

Abstract Genus Acanthopanax is a long-lived woody species that is primarily distributed throughout Asia. Many species of this genus are regarded as medically and ecologically important. We evaluated a representative sample of the nine taxa with allozymes to estimate genetic relationships within the genus. As some Korean populations were isolated and patchily distributed, they exhibited a low level of genetic diversity. The narrow geographic ranges, artificial distribution of habitats, and small population sizes are proposed as factors contributing to low genetic diversity. Acanthopanax seoulense was similar to A. sessiliflorus, while a cluster of the A. rufinerve population is distant from any other species. A. senticosus is closely related to A. seoulense and A. sessiliflorus, whereas other species (A. koreanum) are more distinct from the Korean populations. Korean species are clustered together and clearly differentiated from the Chinese and Russian Acanthopanax taxa, genus Acanthopanax

A genetic, demographic and habitat evaluation of an endangered ephemeral species Xerothamnella herbacea from Australia’s Brigalow belt

2017 ◽  
Vol 65 (1) ◽  
pp. 38 ◽  
Author(s):  
Alison Shapcott ◽  
Robert W. Lamont ◽  
Gabriel Conroy ◽  
Heather E. James ◽  
Yoko Shimizu-Kimura
Keyword(s):  
Genetic Diversity ◽  
Genetic Relationships ◽  
Reproductive Activity ◽  
Suitable Habitat ◽  
Herbaceous Species ◽  
Low Genetic Diversity ◽  
Species Population ◽  
Dry Conditions ◽  
Conservation Assessments ◽  
Clonal Spread

Little remains of the Brigalow (Acacia harpophylla F.Muell. ex Benth.) woodlands of Australia, primarily due to land clearing for grazing and agriculture. Many threatened species in this region are poorly studied, and the life history traits of some herbaceous species such as ephemeral shoot systems, mean that conservation assessments are difficult. Recent gas pipeline developments have led to an increased need to understand the ecology and genetics of such taxa, in order to advise offset and translocation activities. Xerothamnella herbacea R.Baker is an endangered ephemeral herbaceous species from the Brigalow Belt region, which dies back during prolonged dry conditions. The aim of this study was to map the extent of potentially suitable habitat of this species, including determination of population extent within existing protected area estate. The species population sizes, reproductive activity and evidence of clonal spread, as well as the levels of genetic diversity and inbreeding, across the species range were also assessed to provide guidance for potential translocation and offsetting programs. The genetic results were related to the species suitable habitat distribution to test whether historic or recent habitat fragmentation most explains genetic patterns in this species. Most of the populations of this species were found to be small with less than 100 plants. The species appears not to be limited by its reproductive output, suggesting other factors may limit its abundance. The species populations have moderate to low genetic diversity suggesting the species is genetically viable in the medium term but are inbred which may be partially due to vegetative spread. Geographic proximity does not predict genetic similarity of populations and diversity is not correlated with population size. The results indicate potential translocation or offsetting programs need to account for genetic relationships in their planning. Resprouting ability has potentially assisted the species to slow the pace of genetic diversity loss due to anthropogenic fragmentation.

Sign in / Sign up

Export Citation Format

Share Document