What is bone marrow?
Bone marrow is where stem cells that are the ‘building blocks’ of blood can grow into red cells that carry oxygen, white cells that fight infection and platelets that stop bleeding.

Why do we need bone marrow donors?
Bone marrow can be damaged during treatment for leukaemia or a related cancer of the blood, or simply may not function correctly resulting in life threatening forms of anaemia. Since bone marrow is needed to make blood, if a person’s bone marrow is damaged, they will need a stem cell transplant to survive.

How do you find a match?
A matched donor for about 30% of cases can be found from within the patient’s family, but the other 70% need to find a match through a bone marrow registry. Finding a match can be very difficult, so the more people on the registry the better.

Potential donors and patients are matched by comparing the white cells in the blood to reveal their tissue types. As some tissue types are more common in specific ethnic communities, a patient is more likely to be matched with a donor of a similar ethnic background, which increases the chances of a successful transplant.

What is a bone marrow registry?
There are two main bone marrow registries in the UK - the British Bone Marrow Registry and The Anthony Nolan Trust. The British Bone Marrow Registry is part of the National Blood Service and holds details of UK blood donors whom have enrolled as bone marrow donors. It's part of an international network that carries out searches around the world for suitable bone marrow donors.

The Anthony Nolan Trust manages and recruits new bone marrow donors on to the UK's largest bone marrow register. It analyses and manages their database of tissue types and researches ways to make transplantation more successful.

Who can join a bone marrow registry?
People aged 18-50 who are existing blood donors or are willing to donate blood can join a bone marrow registry run by their blood service. You can join when you give blood. A check will be carried out to ensure there are no medical reasons that prevent you from becoming a blood and bone marrow donor. Blood samples will need to be taken so your tissue type can be identified for the registry. You must tell staff before your blood donation if you want to join the bone marrow registry.

If you don't want to give blood but would like to register as a bone marrow donor you can still do so by join the Anthony Nolan Trust, at one or their special bone marrow donor recruitment clinics. You need to be aged between 18 and 40 and give a blood sample at the clinic.

What happens if you join a bone marrow registry?
When you join a registry a letter will be sent out to confirm that your blood sample has been received. When you have been approved to become a bone marrow donor your details and tissue type will be put into a confidential computerised register.

If you're healthy you can generally stay on a registry until your 60th birthday, but let your registry know if there is any health reason that may prevent you from being a donor as you may need to be taken off their list.

What happens if a potential donor match is found?
If a potential donor is found for a patient, the donor will be asked to supply another blood sample for a more detailed tissue typing. There is a one in ten chance that the potential donor will be a match for the patient at this stage.

If the potential donor decides not to go ahead then they can withdraw at any time. However it is important that people remember before they complete the consent form and give a blood sample that becoming a donor is a serious commitment.

What happens if the donor and patient do match?
If the potential donor is identified as the best possible match with the patient then they will be invited to discuss what is involved with the clinical staff.

The potential donor will also be asked to attend a thorough medical examination to make sure that they are fit enough to donate. After the potential donor has given their consent, a number of blood tests will be taken to ensure that the donor is fine to donate and there is going to be no risk to the patient who will receive the donation.

How is a donation carried out?
There are two main ways that a potential donor can donate stem cells – either by donating the bone marrow itself during a simple procedure in hospital or by donating stem cells from the circulating blood using a cell separator machine.

Where are donations made?
Bone marrow donations are collected in hospitals and stem cells are collected at blood centres.

Are there risks in bone marrow donations?
The procedure of bone marrow donation is very safe and any risks involved will be fully explained in the counselling session. However, where a general anaesthetic is administered no medical procedure is completely without any risk. Donating bone marrow and donating stem cells from the circulating blood may cause some temporary discomfort in the bones.

What information will be given about the patient?
All details about the donor and patient, such as their identity and location, will be confidential. The donor will only be told that they are performing an extremely valuable and life-saving procedure for someone else who really needs it.