A patient is heterozygous for sickle-cell anemia. Explain why the patient would have few or no symptoms of sickle-cell anemia
What will be an ideal response
Individuals heterozygous for the sickling gene make both normal and sickling hemoglobin. As a rule these individuals are quite healthy since under reasonable aerobic conditions (at rest and during moderate exercise), the mixed Hb-A and Hb-S still has sufficient O2-carrying capacity and will not sickle, but they can suffer if there is prolonged reduction in blood oxygen levels.
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