There are 2 types of thalassemia: alpha thalassemia and beta thalassemia:
Alpha thalassemia occurs when some or all of the 4 genes that make hemoglobin (the alpha-globin genes) are missing or damaged. You get two from each of your parents. If you inherit:
One mutated gene, you will be a carrier of the disease and you will pass it on to your children. However, you will have no signs or symptoms of thalassemia and your blood tests will most likely be normal. Your red blood cells may be smaller than normal. The thalassemia DNA test can confirm if one is a silent carrier.
Two mutated genes, you will have mild signs and symptoms. This condition might be called alpha-thalassemia trait.
Three mutated genes, your signs and symptoms will be moderate to severe. Symptoms can worsen with fever or exposure to some drugs, chemicals, or infectious agents. Blood transfusions are often needed. You have a greater risk of having a child with alpha thalassemia major. This is also called Haemoglobin H disease.
Four mutated genes: this rarely happens and if it does it usually ends up in stillbirth. Babies born with this condition often die shortly after birth or require lifelong transfusion therapy. In rare cases, a child born with this condition can be treated with transfusions and a stem cell transplant.
The beta hemoglobin chain is manufactured from 2 genes. You get one gene from each of your parents. If you inherit:
One mutated gene, you'll have mild signs and symptoms. This condition is called thalassemia minor or beta-thalassemia.
Two mutated genes, your signs and symptoms will be moderate to severe. This condition is called thalassemia major, or Cooley anemia.
Babies born with two defective beta hemoglobin genes usually are healthy at birth but develop signs and symptoms within the first two years of life. A milder form, called thalassemia intermedia, also can result from two mutated genes.
Thalassemia screening is recommended for the following people:
Anyone with the signs and symptoms above.
Any individual or couple going through assisted reproduction, including IVF.
Family or personal history of thalassemia genetics and inheritance.
People with a family history of a genetic mutation.
High-risk population groups for specific diseases.
Couples who are already pregnant and want to know whether their child has a risk of having a genetic disease.
Any individual wishing to know more about their genetic background.
Sperm and oocyte donors, and recipients of sperm or oocyte donation.
A simple cheek swab sample is needed.
Results come out in 2-3 weeks