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SC235 Unit Three Angela M. Foster, EdD [email protected] AIM: [email protected] AGENDA What is sickle cell anemia? Who is affected by sickle cell anemia? How does sickle cell anemia protect from malaria? Is there a cure? How do those affected avoid complications? Image credits: Microsoft Clip Art Sickle Cell Anemia • The disease is caused by the substitution of a single amino acid in the hemoglobin protein in red blood cells • Causes RBCs to become sickle shaped in low-oxygen situations • Symptoms include physical weakness, pain, organ damage, and even paralysis Image credits: Microsoft Clip Art (a) Normal erythrocyte has normal hemoglobin amino acid sequence in the beta chain. (b) Sickled erythrocyte results from a single amino acid change in the beta chain of hemoglobin. Sickle Cell Disease Is sickle cell a "black“ or “African American” disease? NO! Contrary to popular perception, the gene variant that causes sickle cell not only affects people of African descent, but also people from the Middle East, southern Europe and South Asia. Image credits: Microsoft Clip Art Sickle Cell Disease Why does sickle cell seem to afflict “people of color” more than most other ethnic groups? Why does sickle cell seem to afflict blacks the most? • Sickle cell is found more frequently in persons of Middle Eastern, Indian, Mediterranean and African heritage because those geographic regions are most prone to malaria. • The gene variant for sickle cell disease is related to malaria, not skin color. Image credits: Microsoft Clip Art World Health Organization, 2002 Sickle Cell Disease vs Sickle Cell Anemia • Heterozygous individuals have an intermediate phenotype • Example: Sickling gene -SS = normal Hb is made -Ss = sickle-cell trait (both sickling and normal Hb are made); can suffer a sickle-cell crisis under prolonged reduction in blood O2) -ss = sickle-cell anemia (only sickling Hb is made; more susceptible to sickle-cell crisis) How does the sickle cell trait help people resist malaria? The malaria parasite gains entrance to the bloodstream through a mosquito bite and begins to destroy the normal round-shaped red blood cells that carry oxygen throughout the body. The sickled cell and the parasite are filtered out by the spleen and destroyed, lessening the impact of the parasitic infection. Image credits: Microsoft Clip Art Sickle Cell Disease Is there a CURE for sickle cell anemia? YES! Bone marrow/stem cell transplant can cure sickle cell disease. Bone marrow is a soft, fatty tissue inside the center of the bones where blood cells are made. Image credits: Microsoft Clip Art Vision Checks Vision loss, including blindness, can occur when blood vessels in the eye become blocked with sickle cells and the retina (the thin layer of tissue inside the back of the eye) gets damaged. Image credits: Microsoft Clip Art Avoiding Complication • Get regular checkups • Prevent infections • Get vaccinations •Learn healthy habits •Check out clinical studies •Get support Image credits: Microsoft Clip Art Unit Three – Discussion Board • The consumption of simple carbohydrates, generally in the form of refined sugars, has been on the upswing in the United States for decades now. • You must answer ALL three parts to receive full credit. Image credits: Microsoft Clip Art Lab Project Two – Continued this week • Please continue Lab Project Two by making observations of your Vaseline filter. Be as specific and thorough as possible. -Date, Time, Temperature, Weather conditions, Condition of the filter, AND anything else that you notice about the filter that seems interesting! • Take photos if possible • Use your Data Chart Questions? Image credits: Microsoft Clip Art