Genetic determinants of warfarin maintenance dose and time in therapeutic treatment range: a RE-LY genomics substudy.

AIMS We investigated associations between genetic variation in candidate genes and on a genome-wide scale with warfarin maintenance dose, time in therapeutic range (TTR), and risk of major bleeding. MATERIALS & METHODS In total, 982 warfarin-treated patients from the RE-LY trial were studied. RESULTS After adjusting for SNPs in VKORC1 and CYP2C9, SNPs in DDHD1 (rs17126068) and NEDD4 (rs2288344) were associated with dose. Adding these SNPs and CYP4F2 (rs2108622) to a base model increased R(2) by 2.9%. An SNP in ASPH (rs4379440) was associated with TTR (-6.8% per minor allele). VKORC1 was associated with time less than INR 2.0. VKORC1 and CYP2C9 were associated with time more than INR 3.0, but not with major bleeding. CONCLUSIONS We identified two novel genes associated with warfarin maintenance dose and one gene associated with TTR. These genes need to be replicated in an independent cohort.