Relationships among tributary length, census population size, and genetic variability of white-spotted charr, Salvelinus leucomaenis, in the Lake Biwa water system

Abstract. In order to estimate effective population size, generation interval and the development of inbreeding coefficients (Fx) in three original breeds of cold-blooded horses kept in the Czech Republic: Silesian Noriker (SN), Noriker (N) and Czech-Moravian Belgian horse (CMB) all animals of the particular breeds born from 1990 to 2007 were analysed. The average values of generation interval between parents and their offspring were: 8.53 in SN, 8.88 in N and 8.56 in CMB. Average values of effective population size were estimated to be: 86.3 in SN, 162.3 in N and 104.4 in CMB. The average values of inbreeding coefficient were 3.13 % in SN stallions and 3.39 % in SN mares, in the N breed 1.76 % and 1.26 % and in the CMB breed 3.84 % and 3.26 % respectively. Overall averages of Fx were: 3.23 %, 1.51 % and 3.55 % for the breeds SN, N and CMB. The average value of inbreeding coefficient Fx increased by 1.22 % in SN, by 0.35 % in N and by 1.01 % in CMB, respectively. This may lead to a reduction in genetic variability. Reduction in genetic variability could be either controlled in cooperation with corresponding populations of cold-blooded breeds in other European countries or controlled by number of sires used in population

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IDENTITY COEFFICIENTS IN FINITE POPULATIONS. I. EVOLUTION OF IDENTITY COEFFICIENTS IN A RANDOM MATING DIPLOID DIOECIOUS POPULATION

Genetics ◽

10.1093/genetics/86.3.697 ◽

1977 ◽

Vol 86 (3) ◽

pp. 697-713

Author(s):

C Chevalet ◽

M Gillois ◽

R F Nassar

Keyword(s):

Genetic Variability ◽

Population Size ◽

Effective Population Size ◽

Random Mating ◽

Matrix Multiplication ◽

Inbred Lines ◽

Inbreeding Coefficient ◽

Effective Population ◽

The Mean ◽

Over Time

ABSTRACT Properties of identity relation between genes are discussed, and a derivation of recurrent equations of identity coefficients in a random mating, diploid dioecious population is presented. Computations are run by repeated matrix multiplication. Results show that for effective population size (Ne) larger than 16 and no mutation, a given identity coefficient at any time t can be expressed approximately as a function of (1—f), (1—f)3 and (1—f)6, where f is the mean inbreeding coefficient at time t. Tables are presented, for small Ne values and extreme sex ratios, showing the pattern of change in the identity coefficients over time. The pattern of evolution of identity coefficients is also presented and discussed with respect to N eu, where u is the mutation rate. Applications of these results to the evolution of genetic variability within and between inbred lines are discussed.

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Is genomic diversity a useful proxy for census population size? Evidence from a species‐rich community of desert lizards

Molecular Ecology ◽

10.1111/mec.15042 ◽

2019 ◽

Vol 28 (7) ◽

pp. 1664-1674 ◽

Cited By ~ 3

Author(s):

Maggie R. Grundler ◽

Sonal Singhal ◽

Mark A. Cowan ◽

Daniel L. Rabosky

Keyword(s):

Population Size ◽

Genomic Diversity ◽

Census Population Size

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FAST TRACK: Legacy lost: genetic variability and population size of extirpated US grey wolves (Canis lupus)

Molecular Ecology ◽

10.1111/j.1365-294x.2004.02389.x ◽

2004 ◽

Vol 14 (1) ◽

pp. 9-17 ◽

Cited By ~ 121

Author(s):

JENNIFER A. LEONARD ◽

CARLES VILÀ ◽

ROBERT K. WAYNE

Keyword(s):

Genetic Variability ◽

Population Size ◽

Canis Lupus ◽

Fast Track

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Stable nitrogen and carbon isotope ratios as migration tracers of a landlocked goby, Rhinogobius sp. (the orange form), in the Lake Biwa water system

Ecological Research ◽

10.1046/j.1440-1703.2001.00427.x ◽

2001 ◽

Vol 16 (4) ◽

pp. 697-703 ◽

Cited By ~ 25

Author(s):

Atsushi Maruyama ◽

Yoshihiro Yamada ◽

Masahide Yuma ◽

Bosco Rusuwa

Keyword(s):

Carbon Isotope ◽

Lake Biwa ◽

Water System ◽

Isotope Ratios ◽

Carbon Isotope Ratios

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Mitochondrial DNA Sequence Diversity in Mammals: A Correlation between the Effective and Census Population Sizes

Genome Biology and Evolution ◽

10.1093/gbe/evaa222 ◽

2020 ◽

Vol 12 (12) ◽

pp. 2441-2449

Author(s):

Jennifer James ◽

Adam Eyre-Walker

Keyword(s):

Mitochondrial Dna ◽

Metabolic Rate ◽

Population Size ◽

Effective Population Size ◽

Dna Sequence ◽

Range Size ◽

Effective Population ◽

Population Sizes ◽

Census Population Size ◽

The Relationship

Abstract What determines the level of genetic diversity of a species remains one of the enduring problems of population genetics. Because neutral diversity depends upon the product of the effective population size and mutation rate, there is an expectation that diversity should be correlated to measures of census population size. This correlation is often observed for nuclear but not for mitochondrial DNA. Here, we revisit the question of whether mitochondrial DNA sequence diversity is correlated to census population size by compiling the largest data set to date, using 639 mammalian species. In a multiple regression, we find that nucleotide diversity is significantly correlated to both range size and mass-specific metabolic rate, but not a variety of other factors. We also find that a measure of the effective population size, the ratio of nonsynonymous to synonymous diversity, is also significantly negatively correlated to both range size and mass-specific metabolic rate. These results together suggest that species with larger ranges have larger effective population sizes. The slope of the relationship between diversity and range is such that doubling the range increases diversity by 12–20%, providing one of the first quantifications of the relationship between diversity and the census population size.

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The population genetics of haplo-diploids and X-linked genes

Genetics Research ◽

10.1017/s0016672300026550 ◽

1984 ◽

Vol 44 (3) ◽

pp. 321-341 ◽

Cited By ~ 48

Author(s):

P. J. Avery

Keyword(s):

Population Genetics ◽

Genetic Variability ◽

Population Size ◽

Effective Population Size ◽

Disease Genes ◽

Effective Population ◽

Random Drift ◽

Mutation Pressure ◽

Electrophoretic Data ◽

Fitness Parameters

SUMMARYFrom the available electrophoretic data, it is clear that haplodiploid insects have a much lower level of genetic variability than diploid insects, a difference that is only partially explained by the social structure of some haplodiploid species. The data comparing X-linked genes and autosomal genes in the same species is much more sparse and little can be inferred from it. This data is compared with theoretical analyses of X-linked genes and genes in haplodiploids. (The theoretical population genetics of X-linked genes and genes in haplodiploids are identical.) X-linked genes under directional selection will be lost or fixed more quickly than autosomal genes as selection acts more directly on X-linked genes and the effective population size is smaller. However, deleterious disease genes, maintained by mutation pressure, will give higher disease incidences at X-linked loci and hence rare mutants are easier to detect at X-linked loci. Considering the forces which can maintain balanced polymorphisms, there are much stronger restrictions on the fitness parameters at X-linked loci than at autosomal loci if genetic variability is to be maintained, and thus fewer polymorphic loci are to be expected on the X-chromosome and in haplodiploids. However, the mutation-random drift hypothesis also leads to the expectation of lower heterozygosity due to the decrease in effective population size. Thus the theoretical results fit in with the data but it is still subject to argument whether selection or mutation-random drift are maintaining most of the genetic variability at X-linked genes and genes in haplodiploids.

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