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.