epistasis


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epistasis

 [ĕ-pis´tah-sis]
1. suppression of a secretion or excretion, as of blood, menses, or lochia.
2. the interaction between genes at different loci, as a result of which one hereditary character is unexpressed, or is masked by the superimposition of another upon it. See also dominance. adj., adj epistat´ic.

e·pis·ta·sis

(e-pis'tă-sis),
1. The formation of a pellicle or scum on the surface of a liquid, especially as on standing urine.
2. Phenotypic interaction of nonallelic genes.
3. A form of gene interaction whereby one gene masks or interferes with the phenotypic expression of one or more genes at other loci; the gene the express phenotype of which is said to be "epistatic," whereas the phenotype altered or suppressed is then said to be "hypostatic."
Synonym(s): epistasy
[G. scum; epi- + G. stasis, a standing]

epistasis

(ĭ-pĭs′tə-sĭs)
n. pl. epista·ses (-sēz′)
1. An interaction between nonallelic genes in which the genotype at one locus affects the expression of alleles at another locus.
2. A film that forms over the surface of a urine specimen.
3. The suppression of a bodily discharge or secretion.

ep′i·stat′ic (ĕp′ĭ-stăt′ĭk) adj.

epistasis

[epis′təsis]
Etymology: Gk, a standing
1 suppression of a secretion or excretion, as of blood, menses, or lochia.
2 an interaction between genes at different loci in which one gene masks or suppresses the expression of the other. Epistasis, which is nonallelic and therefore different from dominance, may be caused by the presence of homozygous recessive alleles at one gene pair, as occurs in the Bombay phenotype, or by the presence of a dominant allele at one locus that counteracts the expression of a dominant allele at the other locus. Compare dominance. epistatic, adj.

e·pis·ta·sis

(e-pis'tă-sis)
1. The formation of a pellicle or scum on the surface of a liquid, especially on standing urine.
2. Phenotypic interaction of nonallelic genes.
3. A form of gene interaction whereby one gene masks or interferes with the phenotypic expression of one or more genes at other loci; the gene with the expressed phenotype is said to be epistatic, the phenotype altered or suppressed is then said to be hypostatic.
[G. scum; epi- + G. stasis, a standing]
Epistasisclick for a larger image
Fig. 152 Epistasis . The interaction of genes A and B.

epistasis

a form of genetic interaction in which one gene interferes with the expression of another gene, as when, for example, genes A and B code for enzymes active in the same PATHWAY. See Fig. 152 . If both ALLELES of gene A code for a nonfunctional version of enzyme A, then the pathway will shut down, irrespective of which B alleles are present, i.e. gene A is epistatic to gene B. Compare DOMINANT EPISTASIS, RECESSIVE EPISTASIS.

epistasis,

n gene interaction where a gene at a particular locus supercedes or obscures the expression of another gene at a different locus.

e·pis·ta·sis

(e-pis'tă-sis)
Formation of a pellicle or scum on the surface of a liquid, especially as on standing urine.
[G. scum; epi- + G. stasis, a standing]

epistasis

non-allelic masking of one gene by another, e.g. the masking of the black gene by the orange gene in tortoiseshell cats.
References in periodicals archive ?
Estimation of epistasis among finite polygenic loci for complex traits with a mixed model using Gibbs sampling.
Though gene-gene interactions are expected to play an important role in alcoholism, few studies have investigated epistasis in this disease.
Note that we use the term interaction instead of epistasis because interaction among the sequence variants in one gene can be also easily explained with a strong linkage.
The multiple comparisons problem inherent in this many tests for epistasis was addressed by first calculating the effective number of independent tests for each linkage group (Cheverud 2000, Cheverud 2001).
Moreover, synthesizing our results in the context of biological networks will provide the opportunity to decipher how epistasis and pleiotropy impacted adaptive trajectories.
FMP is a highly complex multimodal problem with strong epistasis and SRP is with numerous local optima and has proven to be an WP-hard problem [41].
1999) Simplex Crossover that works well on functions having multimodality and/or epistasis with a medium number of parents.
A quantitative trait locus genome scan for porcine muscle fiber traits reveals overdominance and epistasis.
The field also includes evolutionary studies, intra-genomic phenomena such as heterosis, epistasis, pleiotropy and other interactions between loci and alleles within the genome (22).