epistasis
Sign in to savethumb|350px|An example of epistasis is the interaction between hair colour and baldness. A gene for Alopecia totalis|total baldness would be epistatic to one for [[blond hair or red hair. The hair-colour genes are hypostatic to the baldness gene. The baldness phenotype supersedes genes for hair colour, and so the effects are non-additive.]] thumb|Example of epistasis in coat colour genetics: If no pigments can be produced the other coat colour genes have no effect on the phenotype, no matter if they are dominant or if the individual is homozygous. Here the genotype "c c" for no pigmentation is
Article
22 sectionsContents
- History
- Classification
- Additivity
- Magnitude epistasis
- Sign epistasis
- Haploid organisms
- Diploid organisms
- Genetic and molecular causes
- Additivity
- Epistasis between genes
- Epistasis within genes
- Heterozygotic epistasis
- Evolutionary consequences
- Fitness landscapes and evolvability
- Evolution of sex
- Methods and model systems
- Regression analysis
- Double mutant cycles
- Computational prediction
- See also
- References
- External links
thumb|350px|An example of epistasis is the interaction between hair colour and baldness. A gene for Alopecia totalis|total baldness would be epistatic to one for [[blond hair or red hair. The hair-colour genes are hypostatic to the baldness gene. The baldness phenotype supersedes genes for hair colour, and so the effects are non-additive.]] thumb|Example of epistasis in coat colour genetics: If no pigments can be produced the other coat colour genes have no effect on the phenotype, no matter if they are dominant or if the individual is homozygous. Here the genotype "c c" for no pigmentation is epistatic over the other genes.
Epistasis is a phenomenon in genetics in which the effect of a gene mutation is dependent on the presence or absence of mutations in one or more other genes, respectively termed modifier genes. In other words, the effect of the mutation is dependent on the genetic background in which it appears. Epistatic mutations therefore have different effects on their own than when they occur together. Originally, the term epistasis specifically meant that the effect of a gene variant is masked by that of a different gene.