Question

An example of a polygene inheritance

Answer 1

Skin Color

The pigment melanin is responsible for dark coloration to the skin.

There are at least three genes, which control for human skin color.

Using an example where the production of melanin is controlled by contributing alleles (denoted here as A, B and C), resulting in dark skin color, and therefore light skin color is produced by non contributing alleles (denoted here as a, b and c), it is possible to see how the spectrum of different skin colors can result in the offspring.

In polygenic inheritance, alleles do not display dominance over others, rather, each contributing allele gives an additive effect rather than a masking effect.

Human Height:

Human height is an extremely complex inheritance pattern as there are over 400 genes controlling for it.

It is therefore extremely difficult to predict the height that an offspring will be.

In addition, height is known as a multifactorial trait, which means that the trait is influenced by multiple genes as well as being affected by the environment.