What does epistases mean?
Epistases is the plural form of epistasis, a term central to classical and modern genetics. An epistasis occurs when the effect of one gene masks, suppresses, or otherwise modifies the expression of a different gene — the interacting gene being described as epistatic to the one it influences. Such interactions were first systematically studied by William Bateson and Reginald Punnett in the early twentieth century, when they observed dihybrid ratios that departed from Mendel's expectations. Geneticists classify epistases into types such as dominant, recessive, duplicate, and reciprocal epistasis, each producing characteristic deviations in offspring ratios. The word derives from the Greek ephistanai, meaning "to stop" or "to stand upon," aptly capturing the idea of one genetic factor standing over another. Though technical, the term is essential reading for anyone studying heredity, quantitative genetics, or evolutionary biology.
nounEpistases is the plural of "epistasis": in genetics, the phenomenon in which the effect of one gene is masked or modified by one or more other genes (called epistatic genes); more broadly, the interaction between genes such that the expression of one depends on another.
- The genetic phenomenon in which the expression of one gene is masked, suppressed, or modified by another gene at a different locus.
- (Rarely) In medicine, an abnormality or morbid state affecting one part of the body as a result of disease elsewhere.
"In these crosses, the epistases between the two loci produced an unexpected 9:3:4 phenotypic ratio."
"The brevity of the coat-colour variation was explained by several epistases acting on the pigment genes."
"Mapping studies revealed complex epistases among quantitative trait loci governing drought tolerance."
"Epistases" is simply the regular Greek-style plural of "epistasis"; use the singular when referring to the phenomenon in general and the plural only when counting distinct instances.
"Several independent epistases were detected across the genome-wide association study."
One gene can literally switch another off — and geneticists call that power grab an epistasis.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of epistases
From Greek ephistanai, "to stand upon" or "to check" (epi-, "upon," plus histanai, "to set or stand"), via New Latin. It entered English in the early twentieth century through the work of geneticists William Bateson and his circle, who coined "epistasis" for the masking of one allelic pair's effect by another. It shares its Greek verbal root with words such as homeostasis, stasis, and static.
Related word forms
How epistases is actually used
A technical term used almost exclusively in genetics and molecular biology literature; the singular "epistasis" is far more common than the plural. The term is formal and scientific register.
Easily confused with epistases
"Epistases" refers to gene interactions that mask or modify other genes' effects, whereas epithelia are sheets of tissue covering body surfaces.
"Epitases" (plural of epitasis) refers in rhetoric to the addition of a concluding clause intensifying what precedes it, while "epistases" is chiefly a genetics term for gene masking.