Biology · Variation and Genetics
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When two or more genes interact in a way that their effect is additive expression, it is;
- A
Co-dominance relation
- B
Polygenic inheritance
- C
Epistasis
- D
Incomplete dominance
Polygenic refers to a trait that is controlled by multiple genes. Such traits are often influenced by the interaction of many genes and environmental factors. In polygenic inheritance, the effect of each gene is additive, meaning that the more genes an individual has for a particular trait, the greater the expression of that trait. For example, human height is a polygenic trait that is influenced by the interaction of many genes. Hence, option B is correct.
Option A is incorrect as Codominance, as it relates to genetics, refers to a type of inheritance in which two versions (alleles) of the same gene are expressed separately to yield different traits in an individual.
This is the correct option.Polygenic refers to a trait that is controlled by multiple genes. Such traits are often influenced by the interaction of many genes and environmental factors. In polygenic inheritance, the effect of each gene is additive, meaning that the more genes an individual has for a particular trait, the greater the expression of that trait.
Option C is incorrect as epistasis refers to the interaction of genes that are not alleles, in particular the suppression of the effect of one such gene by another.
Option D is incorrect as well as Incomplete dominance results from a cross in which each parental contribution is genetically unique and gives rise to progeny whose phenotype is intermediate.
Tagged under Biology · Variation and Genetics · 2022