When a patient's human leukocyte antigen (HLA) and that of a registry member or cord blood unit are almost same, the best marrow transplant results are achieved. It's a lot more difficult than just matching blood types. HLA is a protein that can be found on nearly all of your body's cells. HLA markers are used by your immune system to determine which cells should be in your body and which should not. There are a variety of HLA markers that distinguish a person's tissue type; nevertheless, matching specific markers is crucial for a successful transplant.

What characteristics distinguish a good match?

The HLA types of potential donors and cord blood units are listed on the Be The Match Registry®. People who sign up for the Be The Match Registry swab their cheek to submit a sample of their DNA. A minimum of 6 basic HLA markers are examined in this cheek swab.

Typically, a patient's doctor will select several donors who appear to fit the patient on a fundamental level. Additional testing will be ordered by the doctor for these donors. These in-depth testing will reveal which donor's HLA markers are the most similar to the patient's. Blood testing or extra cheek swabs are the most common tests.

Approximately 8% of members who complete extra tests will donate.

When a member is asked to give, it implies they are the patient's closest HLA match - the best donor.