The symptoms of thalassemia depend upon the number of genes that gets mutated. The inheritance of this disease is through autosomal recessive pattern.
Can You Have Thalassemia And Not Know It?
Thalassemia is the condition occurs due to the genetic mutation of the genes that controls the globin required for the synthesis of hemoglobin. There are six genes controlling the synthesis. Four genes control the expression of alpha globin while 2 genes control the expression of beta globin. The severity of the disease depends upon the number of genes that gets mutated. There are chances that the person may suffer from thalassemia and he may not have the knowledge of the disease. It is due to the fact that the disease may exist in the mild form in the person. Thus, one or two alpha genes or a single beta gene of the person gets mutated. When few genes get mutated, the person may experience either no symptoms or anemia or very mild symptoms which may not require any treatment. The condition is termed as thalassemia minor or thalassemia intermedia and the patients are also the carriers of this disease.
The prognosis of the disease depends upon the severity of the disease and the frequency of blood transfusion required managing the disease. Blood transfusion is the standard treatment of thalassemia but have side effects in the long run. Thus, the patients suffering from mild form of the disease have favorable prognosis as the complications are either absent or very mild. The patients having the severe form of the disease have poor prognosis due to the fact that frequent blood transfusion lead to iron toxicity. However, iron chelating agents have improved the life of such patients.
Types Of Thalassemia
Thalassemia is the blood related condition which is characterized by the production of abnormal hemoglobin. Thalassemia is a genetic condition and is inherited in an autosomal recessive pattern. In some cases, the condition can be inherited as autosomal dominant pattern. There are two types of subunits present in the hemoglobin. One is alpha subunit and the other is beta subunit. Alpha subunit is formed of alpha globin while beta subunit is formed from beta globin. The genes responsible for the synthesis of alpha globin are present on chromosome 16 and are present in two pairs.
The genes responsible for the synthesis of beta globin are present on chromosome 11 and are present in a single pair. Thalassemia can be caused due to the mutation of any of the six genes. The severity of disease can be determined by the number of genes that gets mutated. More the number of genes mutated more the severity of the disease. Following are the types of thalassemia on the basis of number of genes that gets mutated;
- One Alpha Gene Mutation: This is the mildest form of alpha thalassemia and does not have any symptoms. The condition is known as alpha thalassemia minima.
- Two Alpha Gene Mutation: Known as alpha thalassemia minor, this condition has either absent or very mild form of anemia.
- Three Alpha Gene Mutation: Known as hemoglobin H disease or alpha thalassemia intermedia, this condition is characterized by moderate form of the disease and may cause moderate anemia.
- All The Four Alpha Gene Mutation: This condition is known as alpha thalassemia major and is the severest form of alpha thalassemia. This condition is characterized by severe anemia and the unmanaged condition may lead to fatal consequences.
- One Beta Gene Mutation: This condition is known as beta thalassemia minor. It is a mild form of beta thalassemia and the patient may or may not experience the symptoms.
- Both Beta Gene Mutation: This condition is known beta thalassemia major and is the most severe form of beta thalassemia. The patient experiences severe anemia and has the long term consequences. Although properly managed, majority of the patients led a healthy and happy life.
It is possible to have thalassemia without knowing it. If the person has very mild form of disease, there would be no symptoms and the person may not know about the disease.