Some human characteristics, such as height, eye color, and hair color, don't come in just a few distinct forms. Instead, they vary in small gradations, forming a spectrum or continuum of possible phenotypes.

Are polygenic traits continuously varying?

Because multiple genes are involved, polygenic traits do not follow Mendel's pattern of inheritance. Instead of being measured discretely, they are often represented as a range of continuous variation.

How are polygenic traits different?

Usually, traits are polygenic when there is wide variation in the trait. For example, humans can be many different sizes. Height is a polygenic trait, controlled by at least three genes with six alleles. If you are dominant for all of the alleles for height, then you will be very tall.