Thalassemia (from θάλασσα, thalassa, sea + αἷμα, haima, blood; British spelling, "thalassaemia") is an inherited autosomal co-dominant blood disease. In thalassemia, the genetic defect results in reduced rate of synthesis of one of the globin chains that make up hemoglobin. Reduced synthesis of one of the globin chains can cause the formation of abnormal hemoglobin molecules, thus causing anemia, the characteristic presenting symptom of the thalassemias.
Thalassemia is a quantitative problem of too few globins synthesized, whereas sickle-cell anemia (a hemoglobinopathy) is a qualitative problem of synthesis of an incorrectly functioning globin. Thalassemias usually result in underproduction of normal globin proteins, often through mutations in regulatory genes. Hemoglobinopathies imply structural abnormalities in the globin proteins themselves. The two conditions may overlap, however, since some conditions which cause abnormalities in globin proteins (hemoglobinopathy) also affect their production (thalassemia). Thus, some thalassemias are hemoglobinopathies, but most are not. Either or both of these conditions may cause anemia.
The disease is particularly prevalent among Mediterranean people, and this geographical association was responsible for its naming: ''Thalassa (θάλασσα)'' is Greek for the sea, ''Haema (αἷμα)'' is Greek for blood. In Europe, the highest concentrations of the disease are found in Greece and in parts of Italy, in particular, Southern Italy and the lower Po valley. The major Mediterranean islands (except the Balearics) such as Sicily, Sardinia, Malta, Corsica, Cyprus and Crete are heavily affected in particular. Other Mediterranean people, as well as those in the vicinity of the Mediterranean, also have high rates of thalassemia, including Middle Easterners and North Africans. Far from the Mediterranean, South Asians are also affected, with the world's highest concentration of carriers (18% of the population) being in the Maldives.
Recently, increasing reports suggest that up to 5% of patients with beta-thalassemias produce fetal hemoglobin (HbF), and use of hydroxyurea also has a tendency to increase the production of HbF, by as yet unexplained mechanisms.
Giving a happy ending to a poignant family tale and raising fresh hope of leveraging stem cell therapy, a group of doctors and specialists in Chennai and Coimbatore have registered the first successful treatment of thalassaemia in a child using a sibling's umbilical cord blood.
This article is licensed under the Creative Commons Attribution-ShareAlike License.
It uses material from the Wikipedia article on
All material adapted used from Wikipedia is available under the terms of the
Creative Commons Attribution-ShareAlike License.
Wikipedia® itself is a registered trademark of the Wikimedia Foundation, Inc.