HLA and bone marrow transplant donor search strategies

Searching for a family donor other than an HLA identical sibling can be successful. The chance of finding an identical or one antigen mismatched family donor can be calculated with a computer program, so this may help in the decision making whether to perform extended family typing or not. Extended family donors are often better matched rather than unrelated donors. The reason is that they have at least one haplotype genetically identical to the patient, and that there may be some higher match grade for the minor histocompatibility antigens. Sometimes extended family donor could be the only donor for the patient. Ethical considerations have to be taken into account and extended family donors should be volunteer donors.