Related Experiment Video
Updated: Jul 12, 2026
15:00
Daily Transfers, Archiving Populations, and Measuring Fitness in the Long-Term Evolution Experiment with Escherichia coli
Published on: August 18, 2023
Evolution can favor antagonistic epistasis.
Michael M Desai1, Daniel Weissman, Marcus W Feldman
1Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey 08544, USA. mmdesai@princeton.edu
Genetics
|August 28, 2007
Summary
Evolution favors less synergistic epistasis when recombination is present, promoting buffering against harmful mutations. This suggests synergistic epistasis may not be widespread, impacting theories on the advantage of sex.
Area of Science:
- Evolutionary biology
- Genetics
- Theoretical biology
Background:
- Deleterious mutations accumulate and impact evolution through fitness effects, known as epistasis.
- The nature of epistasis (synergistic vs. antagonistic) is crucial for understanding evolution, especially the evolution of sex.
- Experimental evidence on epistasis is currently mixed and inconclusive.
Purpose of the Study:
- To theoretically investigate whether evolution favors synergistic or antagonistic epistasis.
- To determine the extent to which epistasis is favored by evolutionary processes.
Main Methods:
- Theoretical modeling of evolutionary dynamics.
- Analysis of epistasis under conditions of recombination.
Main Results:
- Evolution favors less synergistic or more antagonistic epistasis in the presence of recombination.
- Evolutionary processes promote increased buffering against the fitness effects of deleterious mutations.
Conclusions:
- Synergistic epistasis is unlikely to be widespread in natural populations.
- The mutational deterministic hypothesis for the advantage of sex may have limited applicability due to the prevalence of antagonistic epistasis.
Related Concept Videos
01:09Epistasis Analysis
Although Mendel chose seven unrelated traits in peas to study gene segregation, most traits involve multiple gene interactions that create a spectrum of phenotypes. When the interaction of various genes or alleles at different locations influences a phenotype, this is called epistasis. Epistasis often involves one gene masking or interfering with the expression of another (antagonistic epistasis). Epistasis often occurs when different genes are part of the same biochemical pathway. The...
01:39Epistasis
In addition to multiple alleles at the same locus influencing traits, numerous genes or alleles at different locations may interact and influence phenotypes in a phenomenon called epistasis. For example, rabbit fur can be black or brown depending on whether the animal is homozygous dominant or heterozygous at a TYRP1 locus. However, if the rabbit is also homozygous recessive at a locus on the tyrosinase gene (TYR), it will have an unshaded coat that appears white, regardless of its TYRP1...
01:24Evolution of New Traits in Microbes
Microorganisms evolve rapidly due to their large population sizes and short generation times, often exhibiting measurable changes within days under laboratory conditions. Natural selection acts on standing genetic variation, enabling the retention and amplification of beneficial traits that confer fitness advantages in changing environments.Adaptive Pigment Regulation in RhodobacterIn Rhodobacter, a genus of purple non-sulfur bacteria, light-harvesting pigments such as bacteriochlorophyll and...
02:16Genetics of Speciation
Speciation is the evolutionary process resulting in the formation of new, distinct species—groups of reproductively isolated populations.The genetics of speciation involves the different traits or isolating mechanisms preventing gene exchange, leading to reproductive isolation. Reproductive isolation can be due to reproductive barriers that have effects either before or after the formation of a zygote. Pre-zygotic mechanisms prevent fertilization from occurring, and post-zygotic mechanisms...
01:46Types of Selection
Natural selection influences the frequencies of particular alleles and phenotypes within populations in several different ways. Primarily, natural selection can be directional, stabilizing, or disruptive. Directional selection favors one extreme trait and shifts the population towards that phenotype while selecting against individuals displaying alternate traits. Stabilizing selection favors an intermediate trait with a narrow range of variation. Deviation from the optimal phenotype towards an...
01:38Limits to Natural Selection
Organisms that are well-adapted to their environment are more likely to survive and reproduce. However, natural selection does not lead to perfectly adapted organisms. Several factors constrain natural selection.For one, natural selection can only act upon existing genetic variation. Hypothetically, redtusks may enhance elephant survival by deterring ivory-seeking poachers. However, if there are no gene variants—or alleles—for redtusks, natural selection cannot increase the prevalence of...