It can be confusing to understand the different ways people describe β‑Thalassemiaa genetic blood disorder that reduces or eliminates the production of β‑globin. They are all ways of grouping similar experiences together, but none of them are perfect. Each person with β‑thalassemia is unique and has their own experience of how the disease affects them.


Historically, β‑thalassemia has been classified into three main groups, based on the symptoms a person has and when they first start to show signs of the condition. The three main types are:
People show serious symptoms of disease between the ages of six months and two years; without regular transfusions, most of these people do not survive childhood.
Thalassemia intermedia has a wide spectrum of severity. Some people may show symptoms of disease later than thalassemia major, possibly not until adulthood, and may have no symptoms or have milder symptoms that do not require transfusions or only occasionally require transfusions. Others may show serious symptoms of the disease later in childhood, and require regular transfusions.
Even though these people carry the disease (they may, in fact, be called “carriers”), they usually do not have any symptoms, although some people may experience mild anemia.


β‑thalassemia may also be described as Mediterranean Anemiaa condition where there aren’t enough healthy red blood cells to carry adequate oxygen to the body's tissues or Cooley’s anemia.


Understanding your Genotypeyour genetic makeup for any trait, which may be labelled with a pair of letters, each representing the copy of a gene inherited from one of your parents can be important to help understand and talk about your thal. There are nearly 200 different changes in the HBB gene that can cause β‑thalassemia. The different changes are grouped and represented by one of the letters shown below. When paired, these letters then create a genotype: β0, β+, and βE.  

  • β0: no β‑globin is produced
  • β+: a reduced amount of β‑globin is produced
  • βE: a reduced amount of β‑globin is produced and the type of Hemoglobina protein in your red blood cells that helps carry oxygen throughout your body; healthy adult hemoglobin contains iron and a balanced amount of β‑globin and α-globin is also affected; this genotype is most common in Southeast Asia

People with β‑thalassemia can have any mix of the three genotypes above. They may have two copies of β0 (known as a β00 genotype), one copy (known as a β0/non‑β0 genotype), or no copies of β0 (known as a non-β0/non-β0 genotype).

Your genotype can be determined by a blood test and may help your doctor with treatment decisions. Many people with β‑thalassemia find out their genotype when they are first diagnosed. If you’re not sure what your genotype is, you can ask your doctor.


There are people living with β-thalassemia who receive regular Red Blood Cella hemoglobin-containing cell that carries oxygen throughout your body transfusions to help make up for their lack of healthy red blood cells. Some doctors are starting to categorize β‑thalassemia based on whether or not a person depends on regular blood transfusions to survive and function. If a person needs regular blood transfusions, it is sometimes called transfusion-dependent β‑thalassemia, or TDT. For people who do not receive regular transfusions, the term non-transfusion dependent β-thalassemia (or NTDT) may be used.

To summarize, there are three different ways to describe β‑thalassemia:

  • Three historical types (thalassemia major, thalassemia intermedia, thalassemia minor)

  • Genotypes

  • TDT or non-TDT

Do You Have TDT?

The most straightforward way to talk about your β‑thalassemia may be about whether you receive regular transfusions or not. If you are dependent on transfusions to manage your β‑thalassemia, TDT may be the most direct way to describe your disease.

“Traveling with my husband is the best thing in the world to me. I love that he’s adventurous like me, but I feel like I hold him back because of my thalassemia. I start to get tired when it seems like he could be out for hours. I’m going to talk to my doctor about planning for my tomorrow.”


Doctors can diagnose β‑thalassemia based on symptoms and through the use of blood tests, including complete blood count (CBC) and hemoglobin tests:

  • A CBC measures the amount of hemoglobin and different kinds of blood cells, including white blood cells, platelets, and red blood cells in the blood. People with β‑thalassemia may have fewer and smaller healthy red blood cells and less hemoglobin than normal.

  • Hemoglobin tests measure the types of hemoglobin in a blood sample. Those with β‑thalassemia may show problems with the β‑globin Proteinthe working component of your cells that is required for the structure, function, and regulation of your body's tissues and organs of the hemoglobin.

How is β‑Thalassemia Affecting You?

You may find yourself working hard to balance your work, personal life, and your thal. β‑thalassemia may be having a larger impact on your lifestyle than you realize. Take a short quiz to see how your thal may be affecting your today.

Sign up Today

Learn more ways to help shape your future with β‑thalassemia when you sign up. Start with real-life stories from others living with TDT, continued education on β-thal, and tips for making goals—and sticking to them.