If the individual contains a gene that codes for a specific glycosal transferase that is able to actually form this bond, then they're going to have the A antigen. If they have that specific gene that expresses the glycosal transferase that creates this bond, then they're going to have the B antigen. If they have both genes that basically create both of these glycosyl transferases that form both of these linkages then they're going to have both of these antigens and so they're going to have the blood group AB. On the other hand, if the gene is absent from that individual and the individual cannot synthesize either one of these Glycosyl transferases that can actually form these two types of linkages, then they're not going to be able to form the linkages and so they're going to have this molecule here, this glycoprotein. In that case they're the O blood type. So we see that a specific Glycoly transfer rates must be present in order to add an extra sugar to the galactose of the olymagride sequence.