Final Answer:
Sickle cell anemia is caused by the 1) Substitution of glutamic acid with valine.
Step-by-step explanation:
The primary cause of sickle cell anemia is a point mutation in the gene responsible for producing hemoglobin. This mutation results in the 1)substitution of glutamic acid (hydrophilic) with valine (hydrophobic) in the hemoglobin protein. The altered hemoglobin, known as hemoglobin S (HbS), leads to the formation of abnormal, crescent-shaped red blood cells under certain conditions.
The substitution of glutamic acid with valine changes the properties of the hemoglobin molecule. Glutamic acid is negatively charged and hydrophilic, while valine is neutral and hydrophobic. This alteration disrupts the normal solubility of hemoglobin and causes it to aggregate under low-oxygen conditions, leading to the characteristic sickle-shaped red blood cells.
These distorted cells can block blood vessels, impairing oxygen delivery and causing various complications associated with sickle cell anemia.
Understanding the molecular basis of sickle cell anemia is crucial for comprehending its pathophysiology. The single-point mutation that converts a negatively charged, hydrophilic amino acid to a neutral, hydrophobic one results in significant changes to the structure and function of hemoglobin.
This, in turn, has profound implications for the physical characteristics of red blood cells and the overall health of individuals with sickle cell anemia. In summary, the substitution of glutamic acid with valine due to a point mutation is the root cause of sickle cell anemia.