DPG binds to the tight structure of hemoglobin and prevents Oxygen from binding to the hemoglobin (Hb) in red blood cell. Oxygen is now free to be delivered to your tissues (rather than being stuck in your blood). Increased DPG level would cause a right shift in the Hb-O2 dissociation curve. The "right shift" essentially means that now you'll need more O2 than you needed previously to reach the same % saturation (since you're less attracted to the Hb than you were before). We always do a right shift to get more Oxygen to our tissues.
A good mnemonic for the dissociation curve questions is: CADET, face right! Increased CO2, Acidity, DPG, Exercise, Temperature all lead to a right shift in the dissociation curve and increased O2 delivery to your tissues when tissues need more Oxygen.
Hope that helps! And someone please correct me if i'm wrong 🙂
