The Effect of Demographic Factors and VKORC1 1639 G>A Genotypes on Estimated Warfarin Maintenance Dose in Iranian Patients Under Warfarin Therapy

  • Fariba Rad
  • Mohsen Hamidpour
  • Akbar Dorgalaleh
  • Behzad PoopakEmail author
Original Article


Warfarin is an anticoagulant that inhibits vitamin K-dependent clotting factors including factor (F) II, FVII, FIX and FX. Different factors can change the effect of this anticoagulant in clinic. Therefore we assessed impact of VKORC1 -1639 G>A polymorphism and demographic factors on required maintenance dose in Iranian patients under warfarin therapy. The study population included 95 patients with a mean age of 61.3 ± 12.6 years. Target INR range of 2–3 was considered for these patients. The frequency of VKORC1 -1639 G>A polymorphism was assessed by polymerase chain reaction-restriction length polymorphism (PCR-RFLP). Finally the obtain data were analyzed by SPSS software. Our study revealed that 30.5%, 49.5%, and 20% of the patients had VKORC1 (G/G), (G/A), and (A/A) genotypes, respectively. Carriers of VKORC1 G/G genotype required a higher warfarin dose as compared to A/A carriers (4.48 ± 1.32 and 2.7 ± 1.16 mg/day, respectively; P < 0.01). In addition, patients with higher age required lower warfarin therapeutic dose (r = − 0.3, P < 0.01). It seems that -1639 G>A polymorphism and demographic variables had significant effects on warfarin maintenance dose in Iranian patients under warfarin therapy.


Warfarin Vitamin K epoxide reductase complex subunit 1 Bleeding Thrombosis 



The authors would like to thank Payvand clinical laboratory for supporting our project and Moddares Hospital for their assistance for collected the samples.

Compliance with Ethical Standards

Conflict of interest

The authors declare that they have no conflicting interests. Designed the research, analyzed the data, performed the research and wrote the paper, review and final approval of the version to be published.


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Copyright information

© Indian Society of Hematology and Blood Transfusion 2018

Authors and Affiliations

  • Fariba Rad
    • 1
  • Mohsen Hamidpour
    • 2
  • Akbar Dorgalaleh
    • 3
    • 4
  • Behzad Poopak
    • 5
    Email author
  1. 1.Cellular and Molecular Research CenterYasuj University of Medical SciencesYasujIran
  2. 2.Department of Hematology and Blood Banking, School of Allied Medical SciencesShahid Beheshti University of Medical SciencesTehranIran
  3. 3.Department of Hematology and Blood TransfusionSchool of Allied Medical Sciences, Iran University of Medical SciencesTehranIran
  4. 4.Iranian Comprehensive Hemophilia CenterTehranIran
  5. 5.School of ParamedicineTehran Medical Branch of Islamic Azad UniversityTehranIran

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