When should I start looking for a suitable donor?
If your doctor thinks you may be a candidate for a bone marrow/stem cell transplant in the future, start looking for a donor right away. Only about 3 out of every 10 people can find a matched related donor. And it can take a long time to find a matched unrelated donor if no related donor is available.
How does the search for a matched donor get started?
A well-matched donor is important to the success of your transplant. To look for a donor, your doctor will take a blood sample to test for your human leukocyte antigen (HLA) type. HLA are proteins found on most cells in your body. Your immune system uses these proteins as markers to recognize which cells belong in your body and which do not.
You inherit half of your HLA markers from your mother and half from your father. So each brother and sister with the same parents as you has a 1 in 4 chance of matching you. Your doctor will want to test your brothers and sisters too. Unfortunately, 7 out of 10 of patients who need a transplant don't find a matching donor in their family. If you need an unrelated donor, your primary doctor will enter your HLA data into a computer that searches the data bank of the National Marrow Donor Program (NMDP) and some other registries. This search will look for the best matched donor or umbilical cord blood unit. The best available donor may match some or all of your HLA markers. Some patients who receive unrelated donor transplants have a partially HLA matched donor.