The aim of this study was to investigate whether the VKORC1*3 (rs7294/9041 G > A), VKORC1*4 (rs17708472/6009 C > T), and CYP4F2 (rs2108622/1347 C > T) polymorphisms were associated with elevated warfarin maintenance dose requirements in patients with myocardial infarction (n = 105) from the Warfarin Aspirin Reinfarction Study (WARIS-II). We found significant associations between elevated warfar...

BACKGROUND: The inhibition of the vitamin K cycle by warfarin promotes arterial calcification in the rat. Conceivably, genetically determined vitamin K-deficiency owing to a mutant epoxide reductase subcomponent 1 (Vkorc1) gene, a key component of the vitamin K cycle, might also promote arterial calcification. In the absence of an available Vkorc1 gene knockout model we used a wild-derived Vkor...

Vertebrates possess 2 proteins with vitamin K oxidoreductase (VKOR) activity: VKORC1, whose vitamin K reduction supports vitamin K-dependent (VKD) protein carboxylation, and VKORC1-like 1 (VKORC1L1), whose function is unknown. VKD proteins include liver-derived coagulation factors, and hemorrhaging and lethality were previously observed in mice lacking either VKORC1 or the γ-glutamyl carboxylas...

Anticoagulant rodenticides are commonly used to control rodent pests worldwide. They specifically inhibit the vitamin K epoxide reductase (VKORC1), which is an enzyme encoded by the Vkorc1 gene, involved in the recycling of vitamin K. Therefore, they prevent blood clotting. Numerous mutations of Vkorc1 gene were reported in rodents, and some are involved in the resistant to rodenticides phenoty...

BACKGROUND The management of warfarin therapy is complicated by a wide variation among patients in drug response. Variants in the gene encoding vitamin K epoxide reductase complex 1 (VKORC1) may affect the response to warfarin. METHODS We conducted a retrospective study of European-American patients receiving long-term warfarin maintenance therapy. Multiple linear-regression analysis was used...

BACKGROUND Vitamin K epoxide reductase subunit 1 (VKORC1) is the molecular target of coumarin anticoagulants and mutations in VKORC1 have been identified previously in individuals who required high warfarin doses. OBJECTIVE Detailed characterization of the relationship between variation in VKORC1 and the warfarin resistance phenotype. PATIENTS AND METHODS Serum warfarin concentration and co...

SUMMARY Warfarin-induced bleeding complications and high inter-patient variability are major hindrances to oral anticoagulant therapy. The present study identifies the influence of VKORC1 diplotypes, CYP2C9 and CYP2C19 variants on warfarin disposition and dose requirements in Chinese patients (n=107). The study subjects were genotyped for VKORC1, CYP2C9 and CYP2C19 polymorphic variants. Weekly ...

Polymorphisms in the genes encoding CYP2C9 enzyme and VKORC1 reductase significantly influence the dose variability of coumarinic oral anticoagulants (COAs). Substantial inter- and intraethnic variability exists in the frequencies of CYP2C9*2 and *3 and VKORC1 -1639A alleles. However, the prevalence of CYP2C9 and VKORC1 genetic variants is less characterized in Arab populations. A total of 131 ...

BACKGROUND VKORC1 is reported to be capable of treating several diseases with thrombotic risk, such as cardiac valve replacement. Some single-nucleotide polymorphisms (SNPs) in VKORC1 are documented to be associated with clinical differences in warfarin maintenance dose. This study explored the correlations of VKORC1-1639 G/A, 1173 C/T and 497 T/G genetic polymorphisms with warfarin maintenance...

INTRODUCTION Warfarin is the most commonly used antithrombotic drug. Single nucleotide polymorphisms (SNPs) of CYP2C9, CYP4F2, VKORC1 1173 and VKORC1-1639 influence warfarin maintenance dosage. We aimed to determine the impact of SNPs of these genes on mean daily warfarin dosage (MDWD) in Han-Chinese patients. METHODS Strict literature inclusion criteria were established, and literature searc...