Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Mutations in Microorganisms01:18

Mutations in Microorganisms

445
Mutations are heritable changes in an organism’s genome involving alterations in the base sequence of DNA or RNA. These changes can influence cellular processes and phenotypic traits, potentially transforming the unaltered wild type into a mutant form. Such changes, termed forward mutations, are pivotal in shaping the genetic diversity of organisms.RNA viruses exhibit the highest mutation rates due to the absence of robust proofreading mechanisms during genome replication. In contrast,...
445
Exon Recombination02:32

Exon Recombination

4.0K
The evolution of new genes is critical for speciation. Exon recombination, also known as exon shuffling or domain shuffling, is an important means of new gene formation. It is observed across vertebrates, invertebrates, and in some plants such as potatoes and sunflowers. During exon recombination, exons from the same or different genes recombine and produce new exon-intron combinations, which might evolve into new genes. 
Exon shuffling follows “splice frame rules.” Each exon...
4.0K
Mutation, Gene Flow, and Genetic Drift01:09

Mutation, Gene Flow, and Genetic Drift

61.6K
In a population that is not at Hardy-Weinberg equilibrium, the frequency of alleles changes over time. Therefore, any deviations from the five conditions of Hardy-Weinberg equilibrium can alter the genetic variation of a given population. Conditions that change the genetic variability of a population include mutations, natural selection, non-random mating, gene flow, and genetic drift (small population size).
61.6K
Genome Copying Errors02:46

Genome Copying Errors

5.0K
DNA replication is a well-evolved process that copies millions of base pairs with high fidelity during each cell division. Occasionally a wrong base or a long stretch of wrong bases may get added to the daughter strands. If the errors are left unchecked, cells might accumulate several mutations that might endanger their  survival. Therefore, the copying errors are checked and repaired at three levels.
5.0K
Gene Evolution - Fast or Slow?02:05

Gene Evolution - Fast or Slow?

7.9K
The genomes of eukaryotes are punctuated by long stretches of sequence which do not code for proteins or RNAs. Although some of these regions do contain crucial regulatory sequences, the vast majority of this DNA serves no known function. Typically, these regions of the genome are the ones in which the fastest change, in evolutionary terms, is observed, because there is typically little to no selection pressure acting on these regions to preserve their sequences.
In contrast, regions which code...
7.9K
Gene Conversion02:08

Gene Conversion

10.5K
Other than maintaining genome stability via DNA repair, homologous recombination plays an important role in diversifying the genome. In fact, the recombination of sequences forms the molecular basis of genomic evolution. Random and non-random permutations of genomic sequences create a library of new amalgamated sequences. These newly formed genomes can determine the fitness and survival of cells. In bacteria, homologous and non-homologous types of recombination lead to the evolution of new...
10.5K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Facts and Theories About Muscular Activity.

The Ulster medical journal·2010
Same author

Is the population size of a species relevant to its evolution?

Evolution; international journal of organic evolution·2002
Same author

The neutral theory in an infinite population.

Gene·2001
Same author

Genetic drift in an infinite population. The pseudohitchhiking model.

Genetics·2000
Same author

The role of population size in molecular evolution.

Theoretical population biology·1999
Same author

Junk ain't what junk does: neutral alleles in a selected context.

Gene·1998

Related Experiment Video

Updated: Jan 1, 2026

Following the Dynamics of Structural Variants in Experimentally Evolved Populations
04:52

Following the Dynamics of Structural Variants in Experimentally Evolved Populations

Published on: February 3, 2023

1.3K

Substitution processes in molecular evolution. III. Deleterious alleles

J H Gillespie1

  • 1Section of Evolution and Ecology, University of California, Davis 95616.

Genetics
|November 1, 1994
PubMed
Summary

This study examines deleterious allele evolution models. The house-of-cards model shows that substitutions are not exclusively deleterious, challenging prior claims and suggesting limitations for molecular evolution models.

Area of Science:

  • Evolutionary biology
  • Population genetics
  • Molecular evolution

Background:

  • Deleterious alleles play a crucial role in evolutionary processes.
  • Understanding substitution rates is key to modeling molecular evolution.
  • The house-of-cards model is a widely used framework for studying deleterious allele dynamics.

Purpose of the Study:

  • To analyze substitution processes across different deleterious allele models.
  • To evaluate the validity and applicability of the house-of-cards model.
  • To identify suitable models for silent and protein evolution.

Main Methods:

  • Computer simulations were employed to investigate allele substitution dynamics.
  • Mathematical analyses were used to derive theoretical predictions.

More Related Videos

Generation of Genomic Deletions in Mammalian Cell Lines via CRISPR/Cas9
09:40

Generation of Genomic Deletions in Mammalian Cell Lines via CRISPR/Cas9

Published on: January 3, 2015

96.4K
The Green Monster Process for the Generation of Yeast Strains Carrying Multiple Gene Deletions
13:06

The Green Monster Process for the Generation of Yeast Strains Carrying Multiple Gene Deletions

Published on: December 15, 2012

14.7K

Related Experiment Videos

Last Updated: Jan 1, 2026

Following the Dynamics of Structural Variants in Experimentally Evolved Populations
04:52

Following the Dynamics of Structural Variants in Experimentally Evolved Populations

Published on: February 3, 2023

1.3K
Generation of Genomic Deletions in Mammalian Cell Lines via CRISPR/Cas9
09:40

Generation of Genomic Deletions in Mammalian Cell Lines via CRISPR/Cas9

Published on: January 3, 2015

96.4K
The Green Monster Process for the Generation of Yeast Strains Carrying Multiple Gene Deletions
13:06

The Green Monster Process for the Generation of Yeast Strains Carrying Multiple Gene Deletions

Published on: December 15, 2012

14.7K
  • Various models were compared, including house-of-cards, exponential, gamma shift, Hartl-Dykhuizen-Dean (HDD), and optimum models.

    • Main Results:

    • The substitution rate in the house-of-cards model is a concave function of selection strength (alpha).
    • The house-of-cards model exhibits neutral behavior for alpha < 1 and stagnation for alpha > 4.
    • Contrary to claims, the house-of-cards model involves both deleterious and advantageous substitutions.
    • Only the optimum and HDD models are considered plausible for silent evolution.

    Conclusions:

    • The house-of-cards model is not a model of exclusively deleterious evolution.
    • No biologically plausible models accurately represent exclusively deleterious substitutions in molecular evolution.
    • Current models are inadequate for explaining protein evolution due to biological reasonableness and observed variability.