For example, the high trait or the skin color trait. These different types of traits are affected or controlled by many different pairs of alleles down on different low side. So polygenic inheritance is this phenomenon that basically describes this idea that multiple different allele pairs actually affect and control and have an additive effect on a given type of trait. For example, the hydrate and the skin color trait. Now, to demonstrate what we mean by polygenic inheritance, let's begin by assuming that the skin color trait in humans is controlled by three gene pairs. So we have gene pair A, we have gene pair B and we have gene pair C. Let's suppose that these three different gene pairs are unlinked genes and what that means is they're located on different homologous chromosomes.