A 100% bone marrow match is most likely to be a brother, sister, or another family member. This is because they are more likely to share similar human leukocyte antigens (HLA).
Understanding HLA and Bone Marrow Matching
Human Leukocyte Antigens (HLA) are proteins found on the surface of cells. They play a vital role in the immune system's ability to distinguish between the body's own cells and foreign invaders. For a bone marrow transplant to be successful, the donor's HLA must closely match the recipient's HLA.
Who is a good candidate?
While siblings are often the best candidates for a perfect match, other family members can also be a good match. However, if a family match is not available, then unrelated donors may be screened to find a match, although a perfect match is less likely when the donor is not a family member.
Potential 100% Matches within a Family
| Relationship | Likelihood of Match |
|---|---|
| Brother/Sister | High |
| Other Family Members | Lower, but possible |
| Unrelated Donors | Less likely |
Why is a Close Match Important?
- Reduced Risk of Rejection: A close HLA match minimizes the risk of the recipient’s immune system attacking the donated bone marrow (graft-versus-host disease or GVHD).
- Improved Transplant Success: A better match increases the likelihood that the transplanted bone marrow will successfully engraft and produce healthy new blood cells.
The Challenge of Finding a Match
As the reference states, many patients will not have a suitable family member match. In these cases, it may be necessary to utilize unrelated bone marrow donor registries to find a match.
