However, patients with an UD had a considerably higher risk of GvHD with HRs ranging between 7.0 (CD8+ T-cells, 95%-CI 1.5-32.1) and 22.5 (CD4+ T-cells, 95%-CI 3.7-138.9) compared to patients with a RD. This evidence concerns the gene CD8A and graft versus host disease.