polygene

genetics

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July 1, 2026

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In genetics, a polygene refers to any of a group of nonallelic genes that collectively influence the inheritance of a quantitative trait. These traits, known as polygenic traits, vary in degree rather than kind, unlike traits determined by a single gene. Examples include milk yield in cattle, egg-laying capacity in poultry, and human characteristics like stature, blood pressure, and intelligence.12

Polygenic inheritance means that multiple genes, each having a small effect on the phenotype, work together to determine these continuously varying characteristics. Environmental conditions also significantly impact the expression of polygenic traits. While individual genes contribute, the combined action of several or many genes, along with environmental factors, shapes the final observable trait.234

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heredity
Polygenic inheritance
The greatest difficulties of analysis and interpretation are presented by the inheritance of many quantitative or continuously varying traits. Inheritance of this kind produces variations in degree rather than in kind, in contrast to the inheritance of discontinuous traits resulting from single genes…
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The greatest difficulties of analysis and interpretation are presented by the inheritance of many quantitative or continuously varying traits. Inheritance of this kind produces variations in degree rather than in kind, in contrast to the inheritance of discontinuous traits resulting from single genes…
Read More