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The gene pool is the set of all
gene In biology Biology is the natural science that studies life and living organisms, including their anatomy, physical structure, Biochemistry, chemical processes, Molecular biology, molecular interactions, Physiology, physiological mecha ...

gene
s, or
genetic information A nucleic acid sequence is a succession of bases signified by a series of a set of five different letters that indicate the order of nucleotides Nucleotides are organic molecules consisting of a nucleoside and a phosphate. They serve as monom ...
, in any
population Population typically refers the number of people in a single area whether it be a city or town, region, country, or the world. Governments typically quantify the size of the resident population within their jurisdiction by a process called a ...

population
, usually of a particular
species In biology, a species is the basic unit of biological classification, classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individu ...

species
.


Description

A large gene pool indicates extensive
genetic diversity Genetic diversity is the total number of genetic characteristics in the genetic makeup of a species, it ranges widely from the number of species to differences within species In biology, a species is the basic unit of biological classificati ...
, which is associated with robust populations that can survive bouts of intense
selection Selection may refer to: In science: * Selection (biology) Natural selection is the differential survival and reproduction of individuals due to differences in phenotype right , Here the relation between genotype and phenotype is ill ...
. Meanwhile, low
genetic diversity Genetic diversity is the total number of genetic characteristics in the genetic makeup of a species, it ranges widely from the number of species to differences within species In biology, a species is the basic unit of biological classificati ...
(see
inbreeding Inbreeding is the production of offspring In biology, offspring are the young born of living organism, organisms, produced either by a single organism or, in the case of sexual reproduction, two organisms. Collective offspring may be known as ...
and
population bottleneck A population bottleneck or genetic bottleneck is a sharp reduction in the size of a population due to environmental events such as famines, earthquakes, floods, fires, disease, and droughts; or human activities such as specicide, widespread violen ...

population bottleneck
s) can cause reduced
biological fitness Fitness (often denoted w or ω in population genetics models) is the quantitative representation of natural and sexual selection File:Sexual Selection with Peafowl.gif, 250px, Sexual selection is a form of natural selection where one sex pref ...
and an increased chance of
extinction Extinction is the termination of a kind of organism In biology, an organism () is any organic, life, living system that functions as an individual entity. All organisms are composed of cells (cell theory). Organisms are classified by ...

extinction
, although as explained by
genetic drift Genetic drift (allelic drift or the Sewall Wright effect) is the change in the frequency of an existing gene In biology, a gene (from ''genos'' "...Wilhelm Johannsen coined the word gene to describe the Mendelian_inheritance#History, M ...

genetic drift
new genetic variants, that may cause an increase in the fitness of organisms, are more likely to fix in the population if it is rather small. When all individuals in a population are identical with regard to a particular
phenotypic In genetics Genetics is a branch of biology Biology is the natural science that studies life and living organisms, including their anatomy, physical structure, Biochemistry, chemical processes, Molecular biology, molecular inter ...
trait, the population is said to be 'monomorphic'. When the individuals show several variants of a particular trait they are said to be polymorphic.


History

The Russian geneticist Alexander Sergeevich Serebrovsky first formulated the concept in the 1920s as ''genofond'' (gene fund), a word that was imported to the United States from the Soviet Union by
Theodosius Dobzhansky Theodosius Grygorovych Dobzhansky ( uk, Теодо́сій Григо́рович Добжа́нський; russian: Феодо́сий Григо́рьевич Добржа́нский; January 25, 1900 – December 18, 1975) was a prominent Ukra ...
, who translated it into English as “gene pool.”


Gene pool concept in crop breeding

Harlan and de Wet (1971) proposed classifying each crop and its related species by gene pools rather than by formal taxonomy. #Primary gene pool (GP-1): Members of this gene pool are probably in the same "
species In biology, a species is the basic unit of biological classification, classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individu ...

species
" (in conventional biological usage) and can intermate freely. Harlan and de Wet wrote, "Among forms of this gene pool, crossing is easy; hybrids are generally fertile with good chromosome pairing; gene segregation is approximately normal and
gene transfer Horizontal gene transfer (HGT) or lateral gene transfer (LGT) is the movement of genetic material between unicellular and/or multicellular organisms other than by the ("vertical") transmission of DNA from parent to offspring ( reproduction). ...
is generally easy.". They also advised subdividing each crop gene pool in two: #*Subspecies A: Cultivated races #*Subspecies B: Spontaneous races (wild or weedy) #Secondary gene pool (GP-2): Members of this pool are probably normally classified as different species than the crop species under consideration (the primary gene pool). However, these species are closely related and can cross and produce at least some fertile hybrids. As would be expected by members of different species, there are some reproductive barriers between members of the primary and secondary gene pools: #*hybrids may be weak #*hybrids may be partially sterile #*
chromosomes A chromosome is a long DNA molecule with part or all of the genome, genetic material of an organism. Most eukaryotic chromosomes include packaging proteins called histones which, aided by Chaperone (protein), chaperone proteins, bind to and D ...
may pair poorly or not at all #*recovery of desired
phenotype In genetics Genetics is a branch of biology Biology is the natural science that studies life and living organisms, including their anatomy, physical structure, Biochemistry, chemical processes, Molecular biology, molecular inter ...

phenotype
s may be difficult in subsequent generations #*However, "The gene pool is available to be utilized, however, if the plant breeder or geneticist is willing to put out the effort required." #Tertiary gene pool (GP-3): Members of this gene pool are more distantly related to the members of the primary gene pool. The primary and tertiary gene pools can be intermated, but
gene In biology Biology is the natural science that studies life and living organisms, including their anatomy, physical structure, Biochemistry, chemical processes, Molecular biology, molecular interactions, Physiology, physiological mecha ...

gene
transfer between them is impossible without the use of "rather extreme or radical measures" such as: #*embryo rescue (or embryo culture, a form of plant
organ culture Organ culture is a development from tissue culture Tissue culture is the growth of tissues or cells Cell most often refers to: * Cell (biology), the functional basic unit of life Cell may also refer to: Closed spaces * Monastic cell, a smal ...
) #*induced
polyploidy Polyploidy is a condition in which the cell Cell most often refers to: * Cell (biology), the functional basic unit of life Cell may also refer to: Closed spaces * Monastic cell, a small room, hut, or cave in which a monk or religious recluse ...
(chromosome doubling) #*bridging crosses (e.g., with members of the secondary gene pool).


Gene pool centres

Gene pool centres refers to areas on the earth where important crop plants and domestic animals originated. They have an extraordinary range of the wild counterparts of cultivated plant species and useful tropical plants. Gene pool centres also contain different sub tropical and temperate region species.


See also

*
Biodiversity Biodiversity is the biological variety and Genetic variability, variability of life, life on Earth. Biodiversity is a measure of variation at the Genetics, genetic, species, and ecosystem level. Terrestrial biodiversity is usually greater near ...

Biodiversity
*
Conservation biology Conservation biology is the study of the conservation of nature and of Earth's biodiversity with the aim of protecting species, their habitats, and ecosystems from excessive rates of extinction and the erosion of biotic interactions. It is an int ...
*
Founder effect In population genetics Population genetics is a subfield of genetics Genetics is a branch of biology concerned with the study of genes, genetic variation, and heredity in organisms.Hartl D, Jones E (2005) Though heredity had been observed ...

Founder effect
*
Gene flow In , gene flow (also known as gene migration or geneflow and flow) is the transfer of material from one to another. If the rate of gene flow is high enough, then two populations will have equivalent allele frequencies and therefore can be cons ...

Gene flow
*
Genetic drift Genetic drift (allelic drift or the Sewall Wright effect) is the change in the frequency of an existing gene In biology, a gene (from ''genos'' "...Wilhelm Johannsen coined the word gene to describe the Mendelian_inheritance#History, M ...

Genetic drift
*
Small population size Small may refer to: Science and technology * SMALL Small may refer to: Science and technology * SMALL, an ALGOL-like programming language * Small (anatomy), the lumbar region of the back * Small (journal), ''Small'' (journal), a nano-science pub ...
*
Australian Grains Genebank The Australian Grains Genebank (AGG) is a national center for storing genetic material for plant breeding Plant breeding is the science of changing the traits of plants Plants are mainly multicellular organisms, predominantly photosynth ...


References

{{DEFAULTSORT:Gene Pool Ecology Conservation biology Selection Genetics concepts Classical genetics Population genetics Evolutionary biology Biorepositories