What occurs to hemoglobin molecules in sickle cell disease?

In sickle cell disease, the hemoglobin molecules undergo a mutation that causes them to behave abnormally. Specifically, the mutation results in the substitution of one amino acid in the beta chain of hemoglobin. This change alters the hemoglobin's structure under low-oxygen conditions, leading to the formation of elongated, rigid fibers. These fibers distort red blood cells into a sickle shape, which is characteristic of the disease.

The elongated and rigid nature of these sickle-shaped cells hinders their ability to move freely through blood vessels, which can lead to blockages and reduce blood flow, ultimately causing pain and increasing the risk of infections and other complications. The transformed shape and properties of hemoglobin in sickle cell disease are key factors that contribute to the pathology associated with this condition.