Background: It is suggested that HA-1 mismatching among hematopoietic stem cell transplanted recipients-donors is associated with acute graft-versus-host disease (aGVHD). So the aim of this study was to evaluate HA-1 frequency and examine the correlation between HA-1 disparity and GVHD patients who received transplantation from a HLA-identical sibling.

Samples and Methods: the DNA was extracted from 30 pairs of HLA-A2-positive Iranian recipients-donors with GVHD I-IV and 25 pairs without GVHD. All the patients received HSCT from HLA-identical siblings. HA-1 was detected by SSP-PCR method. The HA-1 typing was performed using SSP method (SSP Minor Histocompatibility Antigen primer sets).

Results: The frequency of HA-1R and HA-1H alleles in patients were 0.55 and 0.45 respectively, and showed no significant difference with these alleles frequency in donors 0.53 and 0.47 respectively (p>0.05). The HA-1 disparity was detected in 8 out of 55 donor/recipient pairs (14.5%). The aGVHD (grades I-IV) occurred in 6 (75%) out of 8 patients but in spite of higher incidence of it in the group of patients with HA-1 incompatibility, it was not statistically significant.

Conclusion: In spite of higher frequency of HA-1 disparity in GVHD+ group our data did not reflect a significant association between the HA-1 disparity and risk of acute GVHD.