Poor association between dihydropyrimidine dehydrogenase (DPYD) genotype and fluoropyrimidine‐induced toxicity in an Asian population

Abstract Objective Dihydropyrimidine dehydrogenase (DPYD) genotype is closely associated with fluoropyrimidine (FP)‐induced toxicities in Caucasian population and European Medicines Agency now recommends DPYD genotype‐based FP dosing strategy. Patients and Methods The current study aimed to investigate their impact on FP‐related toxicities in an Asian population using genome‐wide association study (GWAS) data set from 1364 patients with colon cancer. Results Among 82 variants registered in the Clinical Pharmacogenetics Implementation Consortium, 74 DPYD variants were directly genotyped in GWAS cohort; however, only 7 nonsynonymous DPYD variants (CPIC variants) were identified and none of the four recurrent DPYD variants (DPYD*2A, c.2846A>T, c.1679T>G, c.1236G>A) were included. Seven CPIC variants were investigated for their association with the incidence of FP‐related toxicities; however, none of these variants revealed a significant correlation with FP‐related toxicities. Conclusion These data suggested that the DPYD genotype registered in CPIC plays a minor role in FP‐related toxicities in an Asian population.