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CYP2C19 polymorphism in Korean patients on warfarin therapy

Sukhyang Lee1, Hyun Jin Hwang, Jae-Moon Kim

  • 1Graduate School of Clinical Pharmacy, Sookmyung Women's University, Seoul 140-742, Korea.

Archives of Pharmacal Research
|April 12, 2007
PubMed

Insights

CYP2C19 genetic variations influence warfarin dosage and bleeding risks in Koreans. Higher CYP2C19 allele frequency correlates with increased bleeding complications, impacting warfarin therapy management.

Area of Science:

  • Pharmacogenomics
  • Clinical Pharmacology

Background:

  • Warfarin dosing is complex, influenced by genetic factors.
  • CYP2C19 enzyme activity affects warfarin metabolism.
  • Understanding genetic variations is crucial for personalized medicine.

Purpose of the Study:

  • To investigate the impact of CYP2C19 polymorphism on warfarin dosage.
  • To assess the relationship between CYP2C19 variants and bleeding complications in Koreans.
  • To compare CYP2C19 polymorphism distribution in Asian versus Caucasian populations.

Main Methods:

  • Patient stratification into four groups based on warfarin dose and bleeding.
  • Genotyping for CYP2C19*2 and CYP2C19*3 using restriction fragment length polymorphism.
  • Analysis of International Normalized Ratio (INR) and administered warfarin dosage.

Main Results:

  • Significant differences in administered warfarin dosage were observed despite similar INR.
  • CYP2C19*2 showed higher genetic variation than CYP2C19*3 in Korean patients.
  • A higher allele frequency of CYP2C19 was associated with increased bleeding complications.
  • CYP2C19 polymorphism distribution in Asians is more similar to other Asian populations than to Caucasians.

Conclusions:

  • CYP2C19 genetic variations are critical determinants of warfarin response and bleeding risk in the Korean population.
  • Personalized warfarin therapy considering CYP2C19 genotype is recommended.
  • Further research into pharmacogenomic variations across diverse populations is warranted.

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