CYP2B6 and spondylo-ocular syndrome: In univariate analysis, CYP2B6*6 was associated with higher incidence of SOS if both donor and recipient were wild-type (GG); the multivariate analysis confirmed the significant role of donor genetic contribution: 20.6% (10.6–30.7) of patients transplanted from CYP2B6*6 GG carriers developed mild to severe SOS vs. 4.5% (0.0–10.8) of those transplanted from GT/TT subjects (HR = 3.49; 95% CI = 1.12; 10.88; p = 0.03) [47].