What is the specific amino acid substitution in the beta chains of hemoglobin that leads to sickle-cell anemia?
Explanation
Sickle-cell anemia is a classic example of a molecular disease resulting from a single point mutation. The replacement of the polar glutamate with the nonpolar valine at position 6 of the beta-globin chain creates a hydrophobic 'sticky patch' on the surface of deoxyhemoglobin S, leading to aggregation and fiber formation.
Other questions
What is the primary role of the coordinated nitrogen atoms in the porphyrin ring of the heme group in oxygen-binding proteins?
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