Thalassemia

Overview

Thalassemia is an inherited red blood disorder in which the body has a problem producing hemoglobin, the protein that is responsible for carrying oxygen to the rest of the body.

In thalassemia, the body creates fewer healthy hemoglobin proteins, and fewer healthy red blood cells in the bone marrow. A lack of healthy red blood cells can starve the body’s cells of the oxygen required to produce energy and survive. Fewer red blood cells can lead to anemia.

The treatment for thalassemia depends on the severity of the condition. In minor cases, treatment might not be necessary. One can deal with fatigue by eating a well-balanced diet and exercising regularly. However, more severe cases may necessitate regular blood transfusions.

Symptoms

In some cases, the signs and symptoms of thalassemia may appear at birth or develop within the first two years of life. Patients with only one defective hemoglobin gene can be asymptomatic. However, the signs and symptoms may vary according to the severity and the type of thalassemia. Generally, the signs and symptoms include:

• Fatigue
• Difficulty breathing
• Feeling cold
• Dizziness
• Weakness
• Pale or yellowish skin
• Deformities of the facial bones
• Slow growth or development
• Swelling in the abdomen
• Dark-colored urine

Visit a healthcare provider if any signs and symptoms persist for proper diagnosis and treatment.

Causes

Thalassemia is a blood disorder passed down through families. It is induced by changes in the cell’s DNA that produce hemoglobin, the component in red blood cells that transports oxygen around the body. Hemoglobin is made up of four protein chains: two alpha and two beta chains.
Mutations can impact the alpha and beta chains of hemoglobin molecules. Thalassemia occurs when the production of either the alpha or beta chains is defective or missing, leading in either alpha-thalassemia or beta-thalassemia. The extent of the defect determines the severity of the condition.

The severity of alpha thalassemia depends on the number of functioning alpha globin genes inherited from the parents.

In beta thalassemia, the anemia symptoms and the severity of the disease are determined by the portion of the damaged hemoglobin molecule.

Alpha-thalassemia: Each parent will pass down two genes to a child and the four inherited genes will make up alpha globin protein chains. If a person inherits:

• One mutated or missing gene: also known as the alpha thalassemia minima, he or she may be asymptomatic but is still a silent carrier of the disorder which can infect his or her child.
• Two mutated or missing genes: also known as the alpha thalassemia minor or alpha thalassemia trait, he or she might exhibit mild signs and symptoms.
• Three mutated or missing genes: also known as the Hemoglobin H disease, moderate to severe symptoms may be experienced.
• Four defective or missing alpha genes: although rare, they often result in death. Babies born with this syndrome frequently die shortly after birth, or they might need a lifelong blood transfusion if they survive. A stem cell transplant may also be necessary. This condition is also known as hydrops fetalis with Hemoglobin Barts.

Beta-thalassemia: Each parent will pass down two genes to a child and the four inherited genes will make up beta globin protein chains. If a person inherits:

• One mutated or missing gene: also known as the thalassemia minor or beta-thalassemia, he or she will experience mild symptoms.
• Two mutated or missing genes: it usually results to moderate to severe symptoms. Newborn babies with two mutated beta hemoglobin genes are healthy at birth but begin to show signs and symptoms within the first two years of life.

The moderate form of two-gene mutation of beta thalassemia is known as thalassemia intermedia. The severe version is known as beta thalassemia major or Cooley’s anemia.

Risk factors

The following factors make a person more susceptible to thalassemia:

• Family history of thalassemia: Having a biological parent with a thalassemia trait increases children’s risk of developing thalassemia as the defective hemoglobin is genetically passed down.
• Certain ancestry: Thalassemia affects people with ancestral ties to malaria-endemic regions of the world, such as Africa, Southern Europe, and West, South, and East Asia. The gene mutations that cause thalassemia evolved in humans as partial malaria protection.