A cladistic measure of gene flow inferred from the phylogenies of alleles.

Abstract A method for estimating the average level of gene flow among populations is introduced. The method provides an estimate of Nm, where N is the size of each local population in an island model and m is the migration rate. This method depends on knowing the phylogeny of the nonrecombining segments of DNA that are sampled. Given the phylogeny, the geographic location from which each sample is drawn is treated as multistate character with one state for each geographic location. A parsimony criterion applied to the evolution of this character on the phylogeny provides the minimum number of migration events consistent with the phylogeny. Extensive simulations show that the distribution of this minimum number is a simple function of Nm. Assuming the phylogeny is accurately estimated, this method provides an estimate of Nm that is as nearly as accurate as estimates obtained using FST and other statistics when Nm is moderate. Two examples of the use of this method with mitochondrial DNA data are presented.

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GENE FLOW AND GENETIC DIFFERENTIATION

Genetics ◽

10.1093/genetics/78.3.961 ◽

1974 ◽

Vol 78 (3) ◽

pp. 961-965

Author(s):

P T Spieth

Keyword(s):

Gene Flow ◽

Genetic Differentiation ◽

Population Size ◽

Local Population ◽

Biological Significance ◽

Island Model ◽

Genetic Identity ◽

Biological Interpretation ◽

Different Populations ◽

Stepping Stone Model

ABSTRACT A brief analysis is presented for the effects of gene flow upon genetic differentiation within and between populations generated by mutation and drift. Previous results obtained with the "island" model are developed into a form that lends itself to biological interpretation. Attention is focused upon the effective local population size and the ratio of the genetic identity of two genes in different populations to that of two genes in the same population. The biological significance of this ratio, which is independent of population size, is discussed. Similarities between the results of this model and those of the "stepping-stone" model are noted.

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FST in a hierarchical island model.

Genetics ◽

10.1093/genetics/127.3.627 ◽

1991 ◽

Vol 127 (3) ◽

pp. 627-629 ◽

Cited By ~ 6

Author(s):

M Slatkin ◽

L Voelm

Keyword(s):

Gene Flow ◽

Migration Rate ◽

Inbreeding Coefficient ◽

Island Model ◽

F Statistics

Abstract It is shown that in a hierarchical island model, in which demes within a neighborhood exchange migrants at a much higher rate than do demes in different neighborhoods, hierarchical F statistics introduced by S. Wright can indicate the extent of gene flow within and between neighborhoods. At equilibrium, the within-neighborhood inbreeding coefficient, FSN, is approximately 1/(1 + 4Nm1) where N is the deme size and m1 is the migration rate among demes in the same neighborhood. The between-neighborhood inbreeding coefficient, FNT, is approximately 1/(1 + 4Ndm2) where d is the number of demes in a neighborhood and m2 is the migration rate among demes in different neighborhoods.

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Relationship between migration and DNA polymorphism in a local population.

Genetics ◽

10.1093/genetics/126.1.231 ◽

1990 ◽

Vol 126 (1) ◽

pp. 231-234 ◽

Cited By ~ 1

Author(s):

F Tajima

Keyword(s):

Dna Sequences ◽

Migration Rate ◽

Dna Polymorphism ◽

Local Population ◽

Island Model ◽

Marginal Populations ◽

Stepping Stone ◽

Stepping Stone Model

Abstract The expected amount of DNA polymorphism, measured in terms of the number of nucleotide differences between the two DNA sequences randomly sampled from subpopulations, was studied by using the stepping-stone model and the finite island model, under the assumption that the migration rate is not the same among different subpopulations. The results obtained indicate that the expected amount of DNA polymorphism in the subpopulation with lower migration rate is smaller than that of higher migration rate. This suggests that marginal populations tend to have lower level of DNA polymorphism than central populations if the migration rate in the marginal populations is lower than that of the central populations.

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Inferring contemporary levels of gene flow and demographic history in a local population of the leaf beetle Gonioctena olivacea from mitochondrial DNA sequence variation

Molecular Ecology ◽

10.1111/j.1365-294x.2005.02537.x ◽

2005 ◽

Vol 14 (6) ◽

pp. 1641-1653 ◽

Cited By ~ 13

Author(s):

PATRICK MARDULYN ◽

MICHEL C. MILINKOVITCH

Keyword(s):

Mitochondrial Dna ◽

Gene Flow ◽

Dna Sequence ◽

Sequence Variation ◽

Demographic History ◽

Local Population ◽

Leaf Beetle ◽

Mitochondrial Dna Sequence ◽

Dna Sequence Variation

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Mitochondrial DNA variation within and among populations of the mosquito Aedes albopictus

Genome ◽

10.1139/g91-046 ◽

1991 ◽

Vol 34 (2) ◽

pp. 288-292 ◽

Cited By ~ 37

Author(s):

Srinivas Kambhampati ◽

Karamjit S. Rai

Keyword(s):

Mitochondrial Dna ◽

Genetic Variation ◽

Hong Kong ◽

Gene Flow ◽

Genetic Structure ◽

Aedes Albopictus ◽

Range Expansion ◽

Dna Variation ◽

Restriction Fragment Polymorphism ◽

Mtdna Polymorphism

A survey of restriction fragment polymorphism in mitochondrial DNA (mtDNA) of 17 populations of the mosquito Aedes albopictus was undertaken. The mtDNA size was estimated to be about 17.5 kbp. The level of polymorphism was low, with over 99% of the fragments being shared in common among the 17 populations. Three populations, Mauritius, Singapore, and Hong Kong, contained individuals with both the ancestral and novel mtDNA haplotypes. We conclude that the low level of mtDNA polymorphism in A. albopictus is a result of recent range expansion and that the mixture of haplotypes is a likely result of human-aided gene flow among populations.Key words: mitochondrial DNA, genetic variation, genetic structure, Aedes albopictus.

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Current versus historical population sizes in vertebrate species with high gene flow: a comparison based on mitochondrial DNA lineages and inbreeding theory for neutral mutations.

Molecular Biology and Evolution ◽

10.1093/oxfordjournals.molbev.a040504 ◽

1988 ◽

Cited By ~ 3

Keyword(s):

Mitochondrial Dna ◽

Gene Flow ◽

Vertebrate Species ◽

High Gene Flow ◽

Population Sizes ◽

High Gene ◽

Neutral Mutations

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Inferring population connectivity across the range of the purple-crowned fairy-wren (Malurus coronatus) from mitochondrial DNA and morphology: implications for conservation management

Australian Journal of Zoology ◽

10.1071/zo12093 ◽

2012 ◽

Vol 60 (3) ◽

pp. 199 ◽

Cited By ~ 6

Author(s):

Anja Skroblin ◽

Robert Lanfear ◽

Andrew Cockburn ◽

Sarah Legge

Keyword(s):

Mitochondrial Dna ◽

Gene Flow ◽

Dna Sequences ◽

Genetic Divergence ◽

Conservation Management ◽

Habitat Degradation ◽

Morphological Difference ◽

Population Connectivity ◽

Isolated Populations ◽

The Impact

Knowledge of population structure and patterns of connectivity is required to implement effective conservation measures for the purple-crowned fairy-wren (Malurus coronatus), a threatened endemic of northern Australia. This study aimed to identify barriers to dispersal across the distribution of M. coronatus, investigate the impact that the recent declines may have on population connectivity, and propose conservation actions to maintain natural patterns of gene flow. Analysis of mitochondrial DNA sequences from 87 M. coronatus identified two phylogenetic clusters that corresponded with the phenotypically defined western (M. c. coronatus) and eastern (M. c. macgillivrayi) subspecies. The genetic divergence between these subspecies was consistent with isolation by a natural barrier to gene flow, and supports their separate conservation management. Within the declining M. c. coronatus, the lack of genetic divergence and only slight morphological difference between remnant populations indicates that populations were recently linked by gene flow. It is likely that widespread habitat degradation and the recent extirpation of M. c. coronatus from the Ord River will disrupt connectivity between, and dynamics within, remnant populations. To prevent further declines, conservation of M. coronatus must preserve areas of quality habitat and restore connectivity between isolated populations.

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Genetic variation of microsatellite and mitochondrial DNA markers in broad whitefish (Coregonus nasus) in the Colville and Sagavanirktok rivers in northern Alaska

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f97-062 ◽

1997 ◽

Vol 54 (7) ◽

pp. 1548-1556 ◽

Cited By ~ 45

Author(s):

J C Patton ◽

B J Gallaway ◽

R G Fechhelm ◽

M A Cronin

Keyword(s):

Mitochondrial Dna ◽

Genetic Variation ◽

Gene Flow ◽

Microsatellite Loci ◽

Genetic Relationships ◽

Nuclear Genome ◽

Pcr Amplification ◽

Colville River ◽

Limited Gene Flow ◽

Northern Alaska

There has been concern that a causeway leading to oil production facilities in the Alaskan Beaufort Sea could affect the extent of emigration from, and immigration into, a population of broad whitefish (Coregonus nasus) in the Sagavanirktok River. To assess this, we analyzed the genetic relationships of the broad whitefish populations in the Sagavanirktok River, and the nearest adjacent population, in the Colville River. Three microsatellite loci from the nuclear genome, and the NADH-1 gene of mitochondrial DNA (mtDNA), were analyzed. Diploid genotypes were determined with PCR amplification of the microsatellite loci, and mtDNA genotypes were identified with PCR amplification followed by sequencing of 798 nucleotides. Several alleles were identified at each locus and both populations had high levels of genetic variation. There is significant differentiation of the Sagavanirktok River and Colville River broad whitefish stocks for the three microsatellite loci (FST = 0.031) but not mtDNA (FST < 0.001). Possible explanations for the lower level of differentiation of mtDNA than microsatellites include female-mediated gene flow between populations, skewed sex ratios, natural selection, or mutation. The results indicate that there is limited gene flow between the Colville and Sagavanirktok rivers, which represent semi-isolated spawning populations.

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