So the beta subunits of the normal hemoglobin, as shown in the following diagram, have a polar residue at a six position. And that means the glutamate has no problem interacting with the polar water molecules found in close proximity. Now, let's take a look at this diagram. In this diagram, this is the abnormal beta subunit of the hemoglobin molecule. And instead of having glutamate, we now have Valene. Now, the problem with this is valine is nonpolar, and it doesn't want to interact with the polar water molecules.