Hemoglobinopathies: Sickle Cell Anemia, Thalassemia
Start with the big picture
Sickle cell anemia results from a β-globin substitution that produces HbS. Deoxygenation promotes HbS polymerization and red-cell sickling, contributing to vaso-occlusion and hemolysis. The lesson connects triggers, smear and electrophoresis findings, complications, and management. Thalassemias are quantitative globin-synthesis defects and are organized by affected chain. In α-thalassemia, the number of gene deletions relates to the resulting clinical pattern, from silent carrier states to HbH disease or Hb Bart’s. β-thalassemia reflects reduced or absent β-chain production; major and minor forms differ in severity and laboratory findings. Comparing these disorders highlights how structural versus quantitative defects shape presentation and hemoglobin patterns.
What you'll learn
- Explain how the β⁶ Glu-to-Val substitution leads to HbS polymerization.
- Identify factors that precipitate sickling and describe its major consequences.
- Distinguish α- and β-thalassemia by genetic basis and globin-chain production.
- Relate thalassemia subtypes to clinical features and electrophoresis findings.
Continue your study
Work through the complete notes and reinforce the topic with the study tools available in the full lesson.
