How to Find a Bone Marrow or Stem Cell Donor

How can you find a bone marrow donor or stem cell donor? Bone marrow transplants and peripheral blood stem cell transplants are needed by many people who have cancer and other blood conditions. In some situations, stem cells can be collected from the patient's own blood or marrow and then transplanted back. This is known as an autologous transplant. But often this is not possible and patients must look for a donor for their transplant. This is known as an allogeneic transplant.

Close-up of a person donating blood
PhotoAlto / Odilion Dimie

Who Can Be a Bone Marrow or Stem Cell Donor?

The bone marrow or stem cells for transplant must come from a donor whose cells have the same HLA protein types as the recipient. This is like your blood type, it is inherited. If it isn't matched, the recipient may develop graft-versus-host disease after transplant.

Find a Donor Within Your Family

The HLA combination of the patient is inherited. The chances of a match are highest within the family. An identical twin will have the same genetic makeup as the patient and is a perfect match. Unfortunately, not all patients requiring a transplant have twins. Siblings, brothers and sisters who share the same genetic (blood) parents, also have a fairly high chance of an HLA match.

The chances of finding a match from among all siblings increase with the number of siblings you have. Chances increase from about 25% with a single sibling to 92% with 10 siblings. Parents can also be a match for their children and children for parents. Cousins could be a match although the chances are lower.

Finding Unrelated Donors

Individuals unrelated to the patient may also have matching HLA. The chances of a match are higher with individuals within the same ethnic community. Communities in which marriages are more often confined within it are more likely to have a higher proportion of matching individuals. To find an unrelated donor, it is often necessary to search for matches in bone marrow donor registries.

Marrow Donor Registries

Marrow donor registries are databases that store the HLA details of volunteers willing to donate marrow for an individual for a transplant. These databases can be searched for matches for the patient’s HLA combination. Though the chances of finding a match are one in several thousand, tens of thousands of patients have found unrelated donors from within large donor registries.

Many countries and independent organizations maintain large marrow donor registries. These can be contacted for conducting a search for an HLA match. Here are some links, but you may wish to explore even further to find any new registries that may be developed around the world:

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By Indranil Mallick, MD
 Indranil Mallick, MD, DNB, is a radiation oncologist with a special interest in lymphoma.