Glossary of Terms
Anemia: Anemia is a medical condition in which the red blood cell count or hemoglobin is less than normal.
Blood: Blood is a vital fluid that brings nourishment to the body’s organs and tissues and carries away waste substances. Blood transports oxygen, helps the body fight infection, transports hormones, delivers nutrients and disposes of waste.
Blood Transfusion Therapy: The only available treatment for thalassemia major. Regular blood transfusions greatly contribute to the quality and length of life of patients with thalassemia major, and have been a central aspect of the treatment of thalassemia since the 1960s.
Bone Marrow: The soft blood-forming tissue that fills the cavities of bones and contains fat and immature and mature blood cells, including white blood cells, red blood cells, and platelets. Diseases or drugs that affect the bone marrow can affect the total counts of these cells.
Chromosomes: A great number of genes pinned together in a long piece is called a chromosome. Each human cell (except sperm/egg cells) has two copies of each chromosome, one inherited from the mother and one inherited from the father.
Desferal: Medication for removing or chelating iron from the body. It must be administered slowly by needle, in the vein or under the skin, for eight to 12 hours per day, five to seven days a week.
Exjade: Medication for removing or chelating iron from the body. Exjade is a once-daily pill that is dissolved in a glass of water and consumed by the patient.
Genes: Genes are the biological units of inheritance, the unique blueprints for an individual organism, providing all the biological information needed for controlling growth and development throughout its life.
Hemoglobin: Hemoglobin is the protein molecule in red blood cells that carries oxygen from the lungs to the body’s tissues and returns carbon dioxide from the tissues to the lungs.
Iron Chelation: The removal of excess iron in the body. thalassemia patients who receive regular blood transfusions are left with an excess of iron in their body. There are currently two iron chelation therapies available in Canada – Desferal and Exjade.
Iron Overload: Regular blood transfusions provide thalassemia patients with the red blood cells they need to survive. Once these red blood cells are broken down, however, the body is left with an excess of iron. Although iron is essential to the body, excess iron can lead to organ failure and death.
Platelets: Platelets play a single, crucial role in the blood-they begin the process of coagulation (forming the blood into a clot) to prevent the body from losing blood through a damaged blood vessel.
Red Blood Cells: Red blood cells or erythrocytes (RBCs) make up about 45% of the total volume of blood. The primary function of RBCs is to carry oxygen from the lungs around the body, binding the oxygen to hemoglobin, which it then delivers it to each tissue and cell to keep them healthy and functioning.
Thalassemia: Thalassemia refers to a group of genetically-inherited disorders of the blood. It is not infectious and cannot be passed from one individual to another by personal contact. It is a disorder of the hemoglobin molecules inside the red blood cells, which are inherited. The combination of one gene from the mother and one from the father leads to three different types of thalassemia.
Thalassemia Minor: Thalassemia minor is caused by a mutation in one gene. People with thalassemia minor are known as carriers.
Thalassemia Intermedia: Thalassemia intermedia is caused by one of the more severe thalassemic genes combined with a milder thalassemic gene.
Thalassemia Major: Thalassemia major occurs when a child inherits two mutated genes, one from each parent. Children born with thalassemia major usually develop the symptoms of severe anemia within the first year of life. They lack the ability to produce normal, adult hemoglobin and experience chronic fatigue.
White Blood Cells: White blood cells or leukocytes make up just 1% of blood. They play a vital role, working as the body’s first line of defense against invading infectious agents such as bacteria, viruses, fungi and parasites.