So we can also have uppercase C or lowercase C. Now, what do we mean by an uppercase C and a lowercase C? Well, notice that A, B and C are not complete dominance traits. In fact, they're incompletely dominant genes. And we'll see what that means in just a moment. If you are not sure what we mean by incomplete dominance go back and watch my lecture on incomplete dominance and what it means for genes to be incompletely dominant. So the capital letters represent incompletely dominant genes that express a dark color while our lowercase letters represent incompletely dominant genes that express the light skin color.