The parameters tested by backward–forward and forward–backward elimination techniques to identify independent explanatory variables were the following: recipient’s age, donor’s age, difference of recipient and donor’s age, underlying diagnosis, recipient’s smoking history before LT, recipient’s body mass index (BMI), stage 3 PGD, max cold ischemia time, number of HLA mismatches, induction treatment, maintenance immunosuppression (cyclosporine vs. tacrolimus), Y1 t-AR, Y1 t-infections, Y1 t-CMV infections, DSAs before LT, Y1 DSAs, Y1 DSAs class I, and Y1 DSAs class II. The gene discussed is AR; the disease is cytomegalovirus infection.