(Solved): XI. There are almost 500 naturally occurring variants of hemoglobin. Most are the result of a singl ...

XI. There are almost 500 naturally occurring variants of hemoglobin. Most are the result of a single amino acid substitution in a globin polypeptide chain. Some variants product clinical illness, though not all variants have deleterious effects. Shown is a figure showing some of the ion pairs that stabilize the \( T \) state of deoxyhemoglobin for reference from the textbook. A. Hb Chesapeake: \( \alpha 92( \) Arg \( \rightarrow \) Leu) \( \alpha 1 \beta 2 \) contact (Assume Arg shown above) B. Hb Memphis: substitutes one uncharged polar residue for another of similar size on the surface C. Hb Syracuse: \( \beta 143 \) (His \( \rightarrow \) Pro) at BPG \( \beta \) contact D. Hb Bibba: substitutes a Pro for a Leu involved in an alpha helix E. Hb Kansas: \( \beta 102( \) Asn \( \rightarrow \) Thr) (disrupts hydrogen bonding with Asp of \( R \) state) Choose the letter that best represents the statement. Make your "whys" brief. The \( \mathrm{Hb} \) variant(s) least likely to cause pathological symptoms Why? The variant(s) most likely to show pI values different from that of HbA on an isoelectric focusing gel Why? The variant(s) most likely to show a decrease in BPG binding and an increase in the overall affinity of the Hemoglobin for oxygen Why? The variant(s) most likely to have a p50 greater than \( \mathrm{HbA} \) Why?