SICKLE CELL DISEASE
PBL
The Sickle cell disease is an inherited blood disorder characterized by defective hemoglobin. It affects millions of people throughout the world and approximately 72,000 people in the US. It is present in one in every 500 African-American births.
Normal hemoglobin cells are smooth and round, allowing for ease in moving through blood vessels. Sickle cell hemoglobin molecules are stiff and form into the shape of a sickle or a scythe. They tend to cluster together, and cannot easily move through blood vessels. The cluster causes a blockage and stops the movement of oxygen-carrying blood.
Sickle cells die after about 10 to 20 days, unlike normal hemoglobin cells, which live for up to 120 days. This results in a chronic short supply of red blood cells, which causes anemia.
Chemistry, genetics, biochemistry and mathematics, are the sciences that are studying and treating the sickle cell disease.
While having this disease most of the levels of organization of matter are affected; this is because this disease affects the blood, which is needed in all body functions, so our cells are damaged, as well as, our macromolecules, tissues, organs, organ systems, our whole organism and the rest of the population when it is transmitted from generation to generation.
Our biological macromolecules which are composed by carbon, hydrogen and oxygen are strongly affected. Their main functions are to be a source of energy for the body and to provide structural support. These macromolecules are also known as sugars.
Hemoglobin, the molecule that is affected in this disease, is the iron-containing protein attached to red blood cells that transports oxygen from the lungs to the rest of the body. Hemoglobin bonds with oxygen in the lungs, exchanges it for carbon dioxide, and then transports the carbon dioxide back to the lungs to be exhaled. Hemoglobin has characteristics of both the tertiary and quaternary structures of proteins. Most of the amino acids in hemoglobin form alpha helices, connected by short non-helical segments. In most humans, the hemoglobin molecule is an assembly of four globular protein subunits. Each subunit is composed of a protein chain tightly associated with a non-protein heme group.
Sickle cell disease is an inherited disease caused by a genetic mutation. Genes are found on structures in the cells of our body called chromosomes. There are normally 46 total, or 23 pairs, of chromosomes in each cell of our body. The 11th pair of chromosomes contains a gene responsible for normal hemoglobin production.
A mutation or error in this gene is what causes sickle cell disease. This mutation is thought to have originated in areas of the world where malaria was common, since people with sickle trait do not get malaria. The sickle trait actually protects them from the parasite that causes malaria, which is carried by mosquitoes. Malaria is most often seen in Africa and in the Mediterranean area of Europe.
Children who inherit the genetic mutation from both parents will have sickle cell disease. Children who inherit the mutation from only one parent will not have the disease, but will carry the trait for it and can pass it on to their children.
The new nucleotide alters the codon so as to produce an altered amino acid in the protein product. The replacement of A by T at the 17th nucleotide of the gene for the beta chain of hemoglobin changes the codon GAG (for glutamic acid) to GTG (which encodes valine). Thus the 6th amino acid in the chain becomes valine instead of glutamic acid.
This disease brings within many problems, mostly all organs are affected, due that it’s a blood disease and this fluid moves al around the body. The liver, heart, kidneys, gallstone, eyes, bones, and joints can suffer damage from the abnormal function of the sickle cells and their inability to flow through the small blood vessels correctly. Some symptoms and problems are:
- Anemia
- Pain crisis
- jaundice, or yellowing of the skin, eyes, and mouth
- leg damage
- ulcers
- bone damage
We can't prevent sickle cell anemia because it's an inherited disease. However, people can take steps to reduce its complications. People who are at high risk for sickle cell anemia and are planning to have children may want to consider genetic counseling. A counselor can help them understand the risk of having a child who has the disease and help explain the choices that are available for the couple.
Early diagnosis and prevention of complications is critical in sickle cell disease treatment. Treatment may include:
· pain medications
· drinking plenty of water daily (eight to 10 glasses) or receiving fluid intravenously (to prevent and treat pain crises)
· blood transfusions
· penicillin
· folic acid
· bone marrow transplant
In conclusion all I can say is that sickle cell disease is a very horrible disease and that it has to be treated with the proper treatment. It has to be taken seriously and there should be more improvements in technology so we can reduce or help the majority of the cases of sickle cells disease in the world.
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