What is the main goal of screening polymorphic loci before a bone marrow transplant?

The primary goal of screening polymorphic loci before a bone marrow transplant is to find at least one informative locus. Informative loci refer to genetic markers that display variation between the donor and recipient, allowing for better matching of human leukocyte antigens (HLA). This is crucial in ensuring that the transplant is successful and the recipient's immune system does not reject the donor's cells.

Identifying at least one informative locus helps clinicians assess the compatibility of the donor and recipient tissues. A well-matched donor can significantly reduce the risk of graft-versus-host disease (GVHD) and other complications associated with mismatched transplants. Thus, the presence of polymorphic loci that can provide meaningful information about the genetic differences is fundamental for the successful outcome of the transplant procedure.

While confirming blood compatibility and understanding other factors like donor age may be relevant considerations in the broader context of transplantation, the primary focus on polymorphic loci centers on ensuring immunological compatibility through informative genetic markers.