Pathology The primary defect which leads to sickle cell anemia is – A An abnormality in porphyrin part of hemoglobin B Replacement of glutamate by valine in b-chain of HbA C A nonsence mutation in the b-chain of HbA D Substitution of valine by glutamate in the a-chain of HbA 💡 Explanation The primary defect which leads to sickle cell anemia is - ✓ Correct Answer: B. Replacement of glutamate by valine in b-chain of HbA