Final answer:
Sickle-cell anemia is a genetic disorder caused by abnormal hemoglobin S, leading to sickle-shaped red blood cells that can impede blood flow and cause severe health issues. Red blood cell lifespan is significantly shortened, resulting in symptoms like fatigue and heart murmurs, among other complications.
Step-by-step explanation:
Sickle-Cell Anemia
Sickle-cell anemia is a hereditary blood disorder characterized by the production of an abnormal type of hemoglobin, known as hemoglobin S (HbS). This abnormality leads to the production of red blood cells that have a distinctive sickle or crescent shape, particularly under low oxygen conditions. The sickle-shaped red blood cells are less flexible and can block blood flow by getting stuck in capillaries, leading to a variety of complications including hemolysis (the breakdown of red blood cells), painful episodes, and organ damage.
Individuals with sickle-cell anemia experience a reduction in the lifespan of their red blood cells to less than half the normal duration, approximately 30 days, due to the instability of HbS. The reduced oxygen delivery and excessive hemolysis contribute to symptoms such as fatigue, shortness of breath, and heart murmurs, alongside more severe clinical manifestations like strokes and delayed growth.
It is worth noting that thalassemia and hemolytic disease of the newborn (HDN) are different types of anemia that also involve abnormal hemoglobin but have distinct causes and effects compared to sickle-cell anemia. Thalassemia is mainly a genetic adaptation to malaria prevalent in certain regions, whereas HDN occurs when the immune system of a Rhesus negative mother attacks the red blood cells of her Rhesus positive fetus.