Exploring the Risks of Genetic Similarity Between Donor and Recipient in Human Leukocyte Antigen-Matched Transplantation

Objective: Successful allogeneic hematopoietic stem cell transplantation (HSCT) relies on human leukocyte antigen (HLA) matching. However, whether HLA-matching between donors and recipients increases recipients' risk of genetic disease remains unclear.

Methods: We investigated whether HLA-matched donor cells used for HSCT have similar microsatellite DNA polymorphisms to HSCT recipients at 19 randomly selected loci including CSF1PO, D12S391, D13S317, D16S539, D18S51, D19S433, D21S11, D2S1338, D3S1358, D5S818, D6S1043, D7S820, D8S1179, FGA, PentaD, PentaE, TH01, TPOX, and VWA. We analyzed allele matching at each short tandem repeat (STR) loci in HLA-matched and mismatched (control) groups using binary outcomes and a quantitative numerical method.

Results: The frequencies were similar between the HLA-matched group and the mismatched group for D6S1043. However, the allele matching rate was higher in the HLA-matched group than that in the mismatched group at 14 of the 19 STR loci. Overall, a significant increase in the rate of STR matching was observed in the HLA-matched group compared to the mismatched group (P = .004).

Conclusion: It would be interesting to know if the HLA matched pairs came more often in question than their mismatched counterparts as candidates for fully HLA-matched unrelated HSCT. The actual risk for HSCT donors developing these diseases needs further evaluation.