CYP3A5 polymorphism in Mexican renal transplant recipients and its association with tacrolimus dosing.

Background And Aims: Variability in CYP3A5 expression associated with differences in tacrolimus bioavailability has been documented. The wild-type allele CYP3A5*1 expresses the functional protein, whereas the CYP3A5*3 allele is a splice variant with a premature stop codon and encodes a truncated nonfunctional protein. The aim of the study was to determine the frequency of CYP3A5*1 and CYP3A5*3 in 291 (124 adults, 167 pediatric) Mexican renal transplant recipients, evaluate the tacrolimus dose requirements by genotype and compare genotype frequency data with that of other populations.