AbstractAWe studied 100 renal transplanted patients treated with Tac, 60 of whom had Tac blood levels below (n=39) and above (n=21) the target range (10–15 ng/mL) at 1 week post-transplant. The DNA was subjected to multiplex amplification followed by massive parallel semiconductor sequencing in the Ion Torrent personal genome machine.We found four missense changes, all reported and present in cases above and below the blood Tac target. In addition, we did not find differences in the allele and genotype frequencies for the common rs1045642 polymorphism (p.I1145I) between the groups.Our results suggested that the