Impact of muitidrug resistance 1 gene polymorphisms on Tacrolimus regimen and outcome of grafts in renal transplantation recipients

Abstract

Objective To investigate the effect of the polymorphisms of multidrug resistance 1 (MDR1) C3435T and G2677T on Tacrolimus (Tac) individualized treatment and prognosis of grafts in the renal transplantation recipients (RTRs).Methods One hundred and twenty-seven RTRs who treated with Tac regimen and had a stable graft function were enrolled,and were divided into adjuvant treatment group and non-adjuvant treatment group according to whether given adjuvant drugs to raise Tac trough concentrations. MDR1 C3435T and G2677T SNPs were detected by using sequence specific primers PCR.Tac trough concentrations of whole blood were measured by using enzymelabeled immunosorbent assay.Tac concentration-to-dose ratio (C/D) standardized by body weight was compared according to the various genotypes and haplotypes of MDR1 C3435T and G2677TA SNPs.Results Adjuvant treatment group including 36 recipients had a higher frequency of C genotype of C3435T than un-adjuvant treatment group (68.05％ vs 48.35％,P ＜ 0.01 ). The frequency of G2677TA polymorphisms was of no significant difference between the two group recipients (P＞ 0.05).As to non-adjuvant treatment recipients,the mean Tac DD required and C/D were not significantly different among various polymorphisms of MDR1 G2677T/A and C3435T or various haplotypes (P＞0.05).During A follow-up period of 4 years,13 recipients suffered graft dysfunction in which 84.6％ (11/13) carried 3435C genotype (P＞0.05).Conclusion The frequency of MDR1 C3435T polymorphisms in RTRs is high in the recipients given adjuvant treatment to raise Tac concentrations.Recipients with 3435C genotype were prone to graft dysfunction. Key words: Kidney transplantation; Multidrug resistance-associated proteins; Polymorphism, single nucleotide; Tacrolimus