Thalassemia is a heritable anemia (passed from the parents to the children); therefore, it is not contagious, and provoked by a genetic defect that leads to malformation of the hemoglobin – the protein found inside the red blood cells and responsible for transporting oxygen to all cells, tissues and organs of the body.

Each red blood cell circulating in the blood has 300 million hemoglobin molecules. And each molecule, in its normal situation, is comprised of two chains α (alpha) of globin which are connected to two chains β (beta).

In people with thalassemia, due to one or more mutations in two specific chromosomes (the 11 and 16), the bone marrow ceases production or produces in insufficient amount one of the types of globin chains. If the problem appears in the chromosome 16, there shall be lack of the chains α (alpha) and, in turn, the individual will have the α-thalassemia (alphathalassemia). In case the mutations reach the chromosome 11, the chains β will be absent and the unbalance will lead to β-thalassemia (beta-thalassemia).

There are two major types of thalassemia (the alpha and beta), but in accordance with the amount and feature of the almost one thousand mutations possible and already described in the medicine, involving the chromosome 11 and 16, the production of hemoglobin – or eritropoyesis, from the Greek erytra=red blood cells and poeisis=production – may be affected in greater or lesser degree, provoking reactions of the organism and the need for varied treatments.

The thalassemia was also known as Mediterranean anemia, because most occurrences of cases was initially observed in families from European countries located next to the Mediterranean sea, such as Italia, Greece, Turkey and Lebanon. Here comes the origin of the name: coming from the Greek word "thalassa", which means sea – that is, the anemia usual from countries with sea. Nowadays, with the migrating currents and the miscegenation between the people, the cases are spread by the five continents.

A bit of history

Previously to knowledge on the genes involved in thalassemia, this inheritable anemia was known as Cooley anemia – a tribute to the American pediatrist Thomas Cooley, Who was the first to described, in 1927, the classic signs of the most severe pronouncement of the disease: the major thalassemia.