Polygenic traits are traits that are controlled by more than one gene. For example, height, weight, hair color, skin color (basically anything dealing with color). This allows for a wide range of physical traits.
One good example of these traits is, if height was controlled by one gene A and if AA = 6' and Aa = 5'7" and as = 5', then people would either be 6', 5'7", or 5'. Since height is controlled by more than one gene, a wide range of heights is possible.
Polygenic traits usually produce a continuum of phenotypes. Individual genes of a polygenic trait follow Mendel's laws, but together do not produce Mendelian ratios. A bell shaped curve often describes the distribution of phenotypic classes of a polygenic trait.
They are recognized by their expressions that result from gradation of continuous variation.
Additive effects of two or more separate pair of genes control continuous variation.
The traits are quantified by measuring the variation, rather than counting.
They're different types of phenotypic expression which contributes to different pairs of genes.
These traits are also known as quantitative traits or multifactorial traits. They are controlled by two or more genes at different loci on different chromosomes or it is the trait that is controlled by non-allelic genes. They are known as quantitative traits as their phenotypic expression is dependent on multiple alleles located on different chromosomes.
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