A warfarin‐dosing model in Asians that uses single‐nucleotide polymorphisms in vitamin K epoxide reductase complex and cytochrome P450 2C9

Because of the unique lack of genetic diversity despite the multiethnicity in the Asian population, we hypothesize that single‐nucleotide polymorphisms in cytochrome P450 (CYP) 2C9 (CYP2C9*3) and vitamin K epoxide reductase complex subunit 1 (VKORC1) at position 381, used to infer VKORC1haplotype in combination with demographic factors, can accurately predict warfarin doses. The aims of this study were to derive a pharmacogenetics‐based dosing algorithm by use of retrospective information and to validate it through a data‐splitting method in a separate cohort of equal size.

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