Well, in this particular case, in this case, both of those chromosomes contain one of these alleles each. And so the only type of protein that will be expressed is protein B. In this case, one of the alleles doesn't code for anything and the other allele codes for protein B. And so in these three cases, we're going to have blood group B. And finally, this is the only case in which neither of the proteins will actually be expressed because both of those chromosomes contain this particular allele that doesn't code for either of the two proteins. So now that we know what Codominance is, and the fact that Abo blood group tray follows this mode of inheritance we call Codominance, let's take a look at the following example.