gene pool

(noun)

the complete set of unique alleles that would be found by inspecting the genetic material of every living member of a species or population

Related Terms

Examples of gene pool in the following topics:

  • Population Genetics

    • The gene pool is the sum of all the alleles at all genes in a population.
    • Random events that alter allele frequencies will have a much larger effect when the gene pool is small.
    • Therefore, many different populations, with very different and uniform gene pools, can all originate from the same, larger population.
    • Here are three possible outcomes of the founder effect, each with gene pools separate from the original populations.
    • Define a population gene pool and explain how the size of the gene pool can affect the evolutionary success of a population

  • Gene Flow and Mutation

    • An important evolutionary force is gene flow: the flow of alleles in and out of a population due to the migration of individuals or gametes.
    • Maintained gene flow between two populations can also lead to a combination of the two gene pools, reducing the genetic variation between the two groups.
    • Gene flow strongly acts against speciation, by recombining the gene pools of the groups, and thus, repairing the developing differences in genetic variation that would have led to full speciation and creation of daughter species.
    • Gene flow can occur when an individual travels from one geographic location to another.
    • Explain how gene flow and mutations can influence the allele frequencies of a population

  • Defining Population Evolution

    • Because these individuals can share genes and pass on combinations of genes to the next generation, the collection of these genes is called a gene pool.
    • A single individual cannot evolve alone; evolution is the process of changing the gene frequencies within a gene pool.
    • Therefore, the frequency of a gene may increase in a population through genetic hitchhiking if its proximal genes confer a benefit.
    • Gene flow is the exchange of genes between populations or between species.If the gene pools between two populations are different, the exchange of genes can introduce variation that is advantageous or disadvantageous to one of the populations.
    • In this simulation, there is fixation in the blue gene variation within five generations.

  • Genetic Drift

    • Over successive generation, these selection pressures can change the gene pool and the traits within the population.
    • His offspring may continue to dominate the troop and pass on their genes as well.
    • If one individual of a population of 10 individuals happens to die at a young age before leaving any offspring to the next generation, all of its genes (1/10 of the population's gene pool) will be suddenly lost.
    • In a population of 100, that individual represents only 1 percent of the overall gene pool; therefore, genetic drift has much less impact on the larger population's genetic structure.
    • The bottleneck effect occurs when only a few individuals survive and reduces variation in the gene pool of a population.

  • The Eugenics Movement

    • Eugenics was a field sociological and anthropological study that became popular in the late 19th and early 20th century as a method of preserving and improving the population through cultivation of dominant gene groups.
    • Rather than true science, though, Eugenics was merely an ill-considered social philosophy aimed at improving the quality of the human population by increasing reproduction between those with genes considered desirable – Nordic, Germanic and Anglo-Saxon peoples – and limiting procreation by those whose genetic stock was seen as less favorable or unlikely to improve the human gene pool.
    • These sterilizations were the precursor to the Holocaust, the Nazi attempt at genocide against Jews and other ethnic groups they deemed unfavorable to the human gene pool.
    • A half-cousin of Charles Darwin, Francis Galton founded field of Eugenics and promoted the improvement of the human gene pool through selective breeding.

  • Variations in Size and Number of Genes

    • Nucleotide variation is measured for discrete sections of the chromosomes, called genes.
    • During sexual reproduction, offspring inherit alleles from both parents and these alleles might be slightly different, especially if there has been migration or hybridization of organisms, so that the parents may come from different populations and gene pools.
    • In humans, more proteins are encoded per gene than in other species.
    • The repeat-rich regions contain genes coding for host interaction proteins.
    • This figure represents the human genome, categorized by function of each gene product, given both as number of genes and as percentage of all genes.

  • Web, Network, and Ring of Life Models

    • The recognition of the importance of Horizontal gene transfer (HGT), especially in the evolution of prokaryotes, has caused some to propose abandoning the classic "tree of life" model.
    • The hypothesis is that eukaryotes evolved not from a single prokaryotic ancestor, but from a pool of many species that were sharing genes by HGT mechanisms.
    • The "ring of life" is a phylogenetic model where all three domains of life evolved from a pool of primitive prokaryotes .
    • Using the conditioned reconstruction algorithm, it proposes a ring-like model in which species of all three domains (Archaea, Bacteria, and Eukarya) evolved from a single pool of gene-swapping prokaryotes.
    • According to the "ring of life" phylogenetic model, the three domains of life evolved from a pool of primitive prokaryotes.

  • Antibody Genes and Diversity

    • Complex genetic mechanisms evolved which allow vertebrate B cells to generate a diverse pool of antibodies from relatively few antibody genes.
    • Several complex genetic mechanisms have evolved that allow vertebrate B cells to generate a diverse pool of antibodies from a relatively small number of antibody genes.
    • Several sets of genes are located within each of the three regions.
    • During cell maturation, the B cell will splice out the DNA of all but one of the genes from each region and combine the three remaining genes together to form one VDJ segment.
    • This serves to increase the diversity of the antibody pool and impacts the antibody's antigen-binding affinity.

  • Antibodies: Classes and Affinity Maturation

    • Several complex genetic mechanisms have evolved allowing vertebrate B cells to generate a diverse pool of antibodies from a relatively small number of antibody genes.
    • The region (locus) of a chromosome that encodes an antibody is large and contains several distinct genes for each antibody domain— in humans the locus containing heavy chain genes (IGH) is found on chromosome 14, and the loci containing lambda and kappa light chain genes (IGL and IGK) are found on chromosomes 22 and 2.
    • Combining these genes with an assortment of genes for other antibody domains generates a large cavalry of antibodies (i.e., a high degree of variability).
    • SHM results in approximately one nucleotide change per variable gene, per cell division.
    • As a consequence, any daughter B cells acquire slight amino acid differences in the variable domains of their antibody chains, increasing the diversity of the antibody pool and impacting the antibody's antigen-binding affinity.

  • Aquifex, Thermocrinis, and Related Bacteria

    • The Aquificae phylum is a diverse collection of bacteria found in harsh environments: hot springs, sulfur pools, and thermal ocean vents.
    • They have been found in hot springs, sulfur pools, and thermal ocean vents .
    • The presence of the insertion in the Thermotogae species may be due to a horizontal gene transfer.
    • Comparison of the A. aeolicus genome to other organisms showed that around 16% of its genes originated from the Archaea domain.
    • A. aeolicus is also known as one of the few bacterial species capable of doing gene silencing.