Stem Cell or Bone Marrow Transplants are the only cure for thalassemia. It isn't done in all patients as a matched stem cell donor is required and because of the significant risks involved.

Stem cells are produced in bone marrow, the spongy tissue found in the centre of some bones, and have the ability to develop into different types of blood cells. For a stem cell transplant, stem cells from a healthy donor are given through a drip into a vein. The donor is usually a sibling, who doesn't have thalassaemiaand has been shown to be a match. Each sibling has a 1 in 4 chance of being a match. These cells then start to produce healthy red blood cells to replace the cells affected by thalassemia.

A stem cell transplant is an intensive treatment - that carries a number of risks and a long admission to hospital, on average two months. Patients needs to receive chemotherapy to destroytheir ownbone marrow and this is then replaced with the bone marrow from the healthy donor. The main risk is graft versus host disease, which is a life-threatening problem where the transplanted cells start to attack the other cells in the body.

For people with serious types of thalassemia, the long-term benefits of a stem cell transplant will need to be considered against the possible risks, to help determine whether the treatment is suitable.