What is thalassemia?

Thalassemia is a type of inherited blood disorder which can impair the body’s ability to carry oxygen in the blood.

Thalassemia is a term applied to a range of diseases: you may have heard of alpha thalassemia, beta Thalassemia, thalassemia major or thalassemia trait. While they share a common cause, they can manifest in vastly different ways. So it’s important that if you’ve been told you have thalassemia, that you make sure you know what type it is or, how much your doctor thinks it might affect you.

Thalassemia is caused by a problem with one or both copies of the gene that is responsible for producing hemoglobin – the red substance that fills the red blood cells.

We have two copies of most of the genes in our body, but in people with thalassemia one or both of them may be abnormal. For people with one abnormal gene, their other ‘normal’ copy will mean that they might not even notice they have a problem – these people will likely be asymptomatic. They are said to have thalassemia trait.

However, some people may have two copies of the abnormal gene. Depending on where these genes are ‘located’ in the genetic code they may be said to have alpha or beta thalassemia. Yet thalassemia can affect some people much more than others. Some patients may manage with occasional check-ups, while others may need blood transfusions – sometimes very regularly.

Thalassemia is generally found in people originally from around the Mediterranean, Middle East, India or from parts of south east Asia.

It’s thought that a long time ago, thalassemia may have protected people from malaria – and the distribution of the thalassemia genes seems to map to areas that either now or historically were affected by malaria. But even if you have thalassemia today, you should still follow your doctor’s advice if you’re visiting a malaria-affected region.

Thalassemia can cause anemia – a condition where the body has lower than normal levels of red blood cells.

People with Thalassemia often suffer from anemia. This can make them feel tired, because they have fewer blood cells to carry oxygen around their body. We’ll talk more about this on the next page.

Next: Find out how Thalassemia is diagnosed

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