Genomic variation in the American pika: signatures of geographic isolation and implications for conservation

Abstract Background Distributional responses by alpine taxa to repeated, glacial-interglacial cycles throughout the last two million years have significantly influenced the spatial genetic structure of populations. These effects have been exacerbated for the American pika (Ochotona princeps), a small alpine lagomorph constrained by thermal sensitivity and a limited dispersal capacity. As a species of conservation concern, long-term lack of gene flow has important consequences for landscape genetic structure and levels of diversity within populations. Here, we use reduced representation sequencing (ddRADseq) to provide a genome-wide perspective on patterns of genetic variation across pika populations representing distinct subspecies. To investigate how landscape and environmental features shape genetic variation, we collected genetic samples from distinct geographic regions as well as across finer spatial scales in two geographically proximate mountain ranges of eastern Nevada. Results Our genome-wide analyses corroborate range-wide, mitochondrial subspecific designations and reveal pronounced fine-scale population structure between the Ruby Mountains and East Humboldt Range of eastern Nevada. Populations in Nevada were characterized by low genetic diversity (π = 0.0006–0.0009; θW = 0.0005–0.0007) relative to populations in California (π = 0.0014–0.0019; θW = 0.0011–0.0017) and the Rocky Mountains (π = 0.0025–0.0027; θW = 0.0021–0.0024), indicating substantial genetic drift in these isolated populations. Tajima’s D was positive for all sites (D = 0.240–0.811), consistent with recent contraction in population sizes range-wide. Conclusions Substantial influences of geography, elevation and climate variables on genetic differentiation were also detected and may interact with the regional effects of anthropogenic climate change to force the loss of unique genetic lineages through continued population extirpations in the Great Basin and Sierra Nevada.

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Genomic variation in the American pika: signatures of geographic isolation and implications for conservation

10.21203/rs.3.rs-58074/v2 ◽

2020 ◽

Author(s):

Kelly Brie Klingler ◽

Joshua P Jahner ◽

Thomas L Parchman ◽

Chris Ray ◽

Mary Peacock

Keyword(s):

Genetic Variation ◽

Genetic Structure ◽

Sierra Nevada ◽

Spatial Genetic Structure ◽

Spatial Scales ◽

Thermal Sensitivity ◽

Genomic Variation ◽

Genome Wide ◽

A Genome ◽

American Pika

Abstract Background: Distributional responses by alpine taxa to repeated, glacial-interglacial cycles throughout the last two million years have significantly influenced the spatial genetic structure of populations. These effects have been exacerbated for the American pika (Ochotona princeps), a small alpine lagomorph constrained by thermal sensitivity and a limited dispersal capacity. As a species of conservation concern, long-term lack of gene flow has important consequences for landscape genetic structure and levels of diversity within populations. Here, we use reduced representation sequencing (ddRADseq) to provide a genome-wide perspective on patterns of genetic variation across pika populations representing distinct subspecies. To investigate how landscape and environmental features shape genetic variation, we collected genetic samples from distinct geographic regions as well as across finer spatial scales in two geographically proximate mountain ranges of eastern Nevada. Results: Our genome-wide analyses corroborate range-wide, mitochondrial subspecific designations and reveal pronounced fine-scale population structure between the Ruby Mountains and East Humboldt Range of eastern Nevada. Populations in Nevada were characterized by low genetic diversity (𝜋=0.0006–0.0009; 𝜃W=0.0005–0.0007) relative to populations in California (𝜋=0.0014–0.0019; 𝜃W=0.0011–0.0017) and the Rocky Mountains (𝜋=0.0025–0.0027; 𝜃W=0.0021–0.0024), indicating substantial genetic drift in these isolated populations. Tajima’s D was positive for all sites (D=0.240-0.811), consistent with recent contraction in population sizes range-wide. Conclusions: Substantial influences of geography, elevation and climate variables on genetic differentiation were also detected and may interact with the regional effects of anthropogenic climate change to force the loss of unique genetic lineages through continued population extirpations in the Great Basin and Sierra Nevada.

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Genomic Variation in the American Pika: Signatures of Geographic Isolation and Implications for Conservation

10.21203/rs.3.rs-58074/v1 ◽

2020 ◽

Author(s):

Kelly Brie Klingler ◽

Joshua P Jahner ◽

Thomas L Parchman ◽

Chris Ray ◽

Mary Peacock

Keyword(s):

Genetic Variation ◽

Genetic Structure ◽

Sierra Nevada ◽

Spatial Genetic Structure ◽

Spatial Scales ◽

Thermal Sensitivity ◽

Genomic Variation ◽

Genome Wide ◽

A Genome ◽

American Pika

Abstract Background: Distributional responses by alpine taxa to repeated, glacial-interglacial cycles throughout the last two million years have significantly influenced the spatial genetic structure of populations. These effects have been exacerbated for the American pika (Ochotona princeps), a small alpine lagomorph constrained by thermal sensitivity and a limited dispersal capacity. As a species of conservation concern, long-term lack of gene flow has important consequences for landscape genetic structure and levels of diversity within populations. Here, we use reduced representation sequencing (ddRADseq) to provide a genome-wide perspective on patterns of genetic variation across pika populations representing distinct subspecies. To investigate how landscape and environmental features shape genetic variation, we collected genetic samples from distinct geographic regions as well as across finer spatial scales in two geographically proximate mountain ranges of eastern Nevada. Results: Our genome-wide analyses corroborate range-wide, mitochondrial subspecific designations and reveal pronounced fine-scale population structure between the Ruby Mountains and East Humboldt Range of eastern Nevada. Populations in Nevada were characterized by low genetic diversity (𝜋=0.0006–0.0009; 𝜃W=0.0005–0.0007) relative to populations in California (𝜋=0.0014–0.0019; 𝜃W=0.0011–0.0017) and the Rocky Mountains (𝜋=0.0025–0.0027; 𝜃W=0.0021–0.0024), indicating substantial genetic drift in these isolated populations. Tajima’s D was positive for all sites (D=0.240-0.811), consistent with recent contraction in population sizes range-wide. Conclusions: Substantial influences of geography, elevation and climate variables on genetic differentiation were also detected and may interact with the regional effects of anthropogenic climate change to force the loss of unique genetic lineages through continued population extirpations in the Great Basin and Sierra Nevada.

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Analysis of the spatial genetic structure of Passiflora incarnata in recently disturbed sites

Canadian Journal of Botany ◽

10.1139/b05-014 ◽

2005 ◽

Vol 83 (4) ◽

pp. 420-426 ◽

Cited By ~ 3

Author(s):

Rebecca T Tague ◽

Stephanie A Foré

Keyword(s):

Genetic Variation ◽

Genetic Structure ◽

Spatial Genetic Structure ◽

Spatial Scales ◽

Multilocus Genotype ◽

Long Distance ◽

Short Life Span ◽

Successional Species ◽

Passiflora Incarnata ◽

Coefficient Of Coancestry

In early successional species, short life span and frequent spatial relocation may affect the distribution of genetic variation but the pattern may be altered by reproductive patterns. Passiflora incarnata L. (Passifloraceae), an early successional vine found throughout the southeastern United States, reproduces sexually and asexually through clonal sprouts. We examined the genetic structure of P. incarnata in recently disturbed habitats at three spatial scales: within a patch, among patches separated by 250 m, and between sites separated by 10 km. Genetic variation may be clumped at the scale of neighboring plants if stem resprouting is significant. In each patch, eleven arbitrarily selected plants and their four nearest neighbors were mapped and leaf samples were collected for genetic analysis. The multilocus genotype of each individual for seven polymorphic allozymes was determined. Potential clones were determined by estimating the probability of a second occurrence of each genotype and a multilocus coefficient of coancestry. Data indicated P. incarnata was reproducing primarily sexually. Most of the genetic variation was within a patch with little variation among patches. These data suggest that the genetic structure of this colonizing species was determined by founder effects interacting with long distance pollen movement.Key words: allozymes, passionflower, spatial, genetic structure, early colonizer, Passiflora incarnata.

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Quantitative Trait Loci for the Monoamine-Related Traits Heart Rate and Headless Behavior inDrosophila melanogaster

Genetics ◽

10.1093/genetics/157.1.283 ◽

2001 ◽

Vol 157 (1) ◽

pp. 283-294 ◽

Cited By ~ 2

Author(s):

Kristie Ashton ◽

Ana Patricia Wagoner ◽

Roland Carrillo ◽

Greg Gibson

Keyword(s):

Heart Rate ◽

Genetic Variation ◽

Recombinant Inbred Lines ◽

Model Organism ◽

Interval Mapping ◽

Activity Levels ◽

Environmental Variance ◽

Genome Wide ◽

A Genome ◽

Monoamine Receptors

AbstractDrosophila melanogaster appears to be well suited as a model organism for quantitative pharmacogenetic analysis. A genome-wide deficiency screen for haploinsufficient effects on prepupal heart rate identified nine regions of the genome that significantly reduce (five deficiencies) or increase (four deficiencies) heart rate across a range of genetic backgrounds. Candidate genes include several neurotransmitter receptor loci, particularly monoamine receptors, consistent with results of prior pharmacological manipulations of heart rate, as well as genes associated with paralytic phenotypes. Significant genetic variation is also shown to exist for a suite of four autonomic behaviors that are exhibited spontaneously upon decapitation, namely, grooming, grasping, righting, and quivering. Overall activity levels are increased by application of particular concentrations of the drugs octopamine and nicotine, but due to high environmental variance both within and among replicate vials, the significance of genetic variation among wild-type lines for response to the drugs is difficult to establish. An interval mapping design was also used to map two or three QTL for each behavioral trait in a set of recombinant inbred lines derived from the laboratory stocks Oregon-R and 2b.

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Significant genetic differences among Heterodera schachtii populations within and among sugar beet production areas

Nematology ◽

10.1163/15685411-00003297 ◽

2020 ◽

Vol 22 (2) ◽

pp. 165-177 ◽

Cited By ~ 1

Author(s):

Rasha Haj Nuaima ◽

Johannes Roeb ◽

Johannes Hallmann ◽

Matthias Daub ◽

Holger Heuer

Keyword(s):

Genetic Variation ◽

Genetic Structure ◽

Population Genetic Structure ◽

Population Genetic ◽

Spatial Scales ◽

Geographic Distance ◽

Heterodera Schachtii ◽

Parasitic Nematodes ◽

Neutral Genetic Variation ◽

Production Areas

Summary Characterising the non-neutral genetic variation within and among populations of plant-parasitic nematodes is essential to determine factors shaping the population genetic structure. This study describes the genetic variation of the parasitism gene vap1 within and among geographic populations of the beet cyst nematode Heterodera schachtii. Forty populations of H. schachtii were sampled at four spatial scales: 695 km, 49 km, 3.1 km and 0.24 km. DGGE fingerprinting showed significant differences in vap1 patterns among populations. High similarity of vap1 patterns appeared between geographically close populations, and occasionally among distant populations. Analysis of spatially sampled populations within fields revealed an effect of tillage direction on the vap1 similarity for two of four studied fields. Overall, geographic distance and similarity of vap1 patterns of H. schachtii populations were negatively correlated. In conclusion, the population genetic structure was shaped by the interplay between the genetic adaptation and the passive transport of this nematode.

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Genetic variation rs10484761 on 6p21.1 derived from a genome-wide association study is associated with gastric cancer survival in a Chinese population

Gene ◽

10.1016/j.gene.2013.11.087 ◽

2014 ◽

Vol 536 (1) ◽

pp. 59-64 ◽

Cited By ~ 10

Author(s):

Meiyun Kang ◽

Xiaojie Ding ◽

Ming Xu ◽

Haixia Zhu ◽

Sang Liu ◽

...

Keyword(s):

Gastric Cancer ◽

Genetic Variation ◽

Association Study ◽

Chinese Population ◽

Genome Wide Association Study ◽

Cancer Survival ◽

Genome Wide Association ◽

Genome Wide ◽

A Genome

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Effects of seed dispersal, adult tree and seedling density on the spatial genetic structure of regeneration at fine temporal and spatial scales

Tree Genetics & Genomes ◽

10.1007/s11295-010-0313-y ◽

2010 ◽

Vol 7 (1) ◽

pp. 37-48 ◽

Cited By ~ 32

Author(s):

Fabrice Sagnard ◽

Sylvie Oddou-Muratorio ◽

Christian Pichot ◽

Giovanni G. Vendramin ◽

Bruno Fady

Keyword(s):

Genetic Structure ◽

Seed Dispersal ◽

Spatial Genetic Structure ◽

Spatial Scales ◽

Seedling Density ◽

Adult Tree ◽

Temporal And Spatial

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Spatial genetic structure of the sea sandwort (<i>Honckenya peploides</i>) on Surtsey: an immigrant's journey

Biogeosciences ◽

10.5194/bg-11-6495-2014 ◽

2014 ◽

Vol 11 (22) ◽

pp. 6495-6507 ◽

Cited By ~ 3

Author(s):

S. H. Árnason ◽

Ǽ. Th. Thórsson ◽

B. Magnússon ◽

M. Philipp ◽

H. Adsersen ◽

...

Keyword(s):

Genetic Variation ◽

Genetic Structure ◽

Early Stage ◽

Isolation By Distance ◽

Spatial Genetic Structure ◽

Rapid Expansion ◽

Aflp Markers ◽

Plant Colonization ◽

Southern Coast ◽

Binary Matrix

Abstract. Sea sandwort (Honckenya peploides) was one of the first plants to successfully colonize and reproduce on the volcanic island Surtsey, formed in 1963 off the southern coast of Iceland. Using amplified fragment length polymorphic (AFLP) markers, we examined levels of genetic variation and differentiation among populations of H. peploides on Surtsey in relation to populations on the nearby island Heimaey and from the southern coast of Iceland. Selected populations from Denmark and Greenland were used for comparison. In addition, we tested whether the effects of isolation by distance could be seen in the Surtsey populations. Using two primer combinations, we obtained 173 AFLP markers from a total of 347 plant samples. The resulting binary matrix was then analysed statistically. The main results include the following: (i) Surtsey had the highest proportion of polymorphic markers as well as a comparatively high genetic diversity (55.5% proportion of polymorphic loci, PLP; 0.1974 HE) and Denmark the lowest (31.8% PLP; 0.132 HE), indicating rapid expansion during an early stage of population establishment on Surtsey and/or multiple origins of immigrants; (ii) the total genetic differentiation (FST) among Surtsey (0.0714) and Heimaey (0.055) populations was less than half of that found among the mainland populations in Iceland (0.1747), indicating substantial gene flow on the islands; (iii) most of the genetic variation (79%, p < 0.001) was found within localities, possibly due to the outcrossing and subdioecious nature of the species; (iv) a significant genetic distance was found within Surtsey, among sites, and this appeared to correlate with the age of plant colonization; and (v) the genetic structure analysis indicated multiple colonization episodes on Surtsey, whereby H. peploides most likely immigrated from the nearby island of Heimaey and directly from the southern coast of Iceland.

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