Thalassemia, also referred as Familial Mediterranean Anemia, occurs secondary to decreased production of protein chain of hemoglobin molecule, which is caused by an abnormality in the hemoglobin-producing gene. Depending on severity of abnormality in hemoglobin-producing genes, protein is not produced or produced insufficiently. Those abnormalities are manifested in thalassemia at varying severity levels.
First one is thalassemia trait. Normally, human beings have 23 pairs of chromosomes, or human beings have a pair of each gene. There are also 2 hemoglobin-producing genes. If disease is carried through only one, then the person becomes carrier. The person has no complaint; this condition is incidentally diagnosed on complete blood count, which is analyzed for various reasons, and the condition is characterized with minimal anemia, small sized erythrocytes and normal or elevated erythrocyte count.
Thalassemia is called by our population as Familial Mediterranean Anemia. As the name implies, it is a hereditary disease. It is inherited from parents. It is common at Mediterranean geography and it is associated with anemia.
How it occurs?
First of all, we have to talk about the structure of hemoglobin. The molecule “hemoglobin” gives red color to our blood and carries oxygen to our tissues. This molecule consists of two parts. One is iron “Hem” part, and the other one is protein “Globin” part. Globin part, made of protein, is comprised of 2 protein chains. Hemoglobin A is the most common type of hemoglobin in adults. Hemoglobin A consists of 2 Alpha and 2 Beta protein chains. The disease is named to refer impaired globin chain. If Beta chain is impaired, the disease is called Beta-thalassemia, or if Alpha chain is impaired, then the disease is called Alpha-thalassemia, and thalassemia also refers less common impairment of other hemoglobin types, such as FA2, albeit rare. Impairment of hemoglobin-producing gene is necessary for any abnormality of those chains. As a result of this impairment, whether familial or acquired, production of protein chains will decrease, resulting with different types of the disease, which vary in terms of severity.