BIOLOGY 3 Lecture Notes - Lecture 22: East Los Angeles College, Asplenia, Priapism
Document Summary
Sickle cell disease is caused by a single mutation on the hbb gene, this results in the coding of a valine amino acid instead of the normal glutamic acid. When only one copy of the hbs allele is inherited the symptoms can be mild or nearly non-existent but when an individual is homozygous for hbs they can develop the disease. The clinical course of sickle cell anemia does not follow a single pattern: some patients have mild symptoms and some have very severe symptoms. The basic problem, however, is the same: the sickle-shaped red blood cells tend to get stuck in narrow blood vessels, blocking the flow of blood that results in a vaso-occlusive crisis. When small blood vessels in hands or feet are blocked, pain and swelling can result, along with fever. This may be the first symptom of sickle cell anemia in infants as early as six months of age and may occur in children with sickle trait.
