Association of CYP2C9 Single Nucleotide Polymorphisms with Warfarin Dose Requirements: A Study in Iraqi Patients
DOI:
https://doi.org/10.22317/jcms.v11i3.1886Keywords:
Warfarin, Anticoagulation therapy, CYP2C9 gene, SNPs, rs1799853, rs1057910.Abstract
Objectives: This study investigates the impact of two single nucleotide polymorphisms (SNPs) in the CYP2C9 gene—CYP2C92 (rs1799853) and CYP2C93 (rs1057910)—on warfarin metabolism. These variants affect the activity of the cytochrome P450 2C9 enzyme, which is responsible for warfarin clearance. We analyzed the genotypes and corresponding weekly warfarin doses in Iraqi patients, alongside demographic and clinical factors influencing dose variability.
Methods: The studied group consisted of 97 Iraqi individuals receiving stable warfarin treatment. Genotyping was performed by using Allele-Specific PCR for identifying the polymorphisms of the CYP2C9 gene, the CYP2C9*2 and CYP2C9*3 alleles since they are associated with warfarin clearance. The groups were categorized as wild type, heterozygous and mutant.
Result: The wild-type genotype (CC) of the CYP2C9*2 (rs1799853) was the most common in this study accounting for 73.2% of the participants. Heterozygous genotype (CT) was found in 24.7% while mutant type was (TT) at about 2.1%. CYP2C9*3 (rs1057910) the wild type(AA) was the most common in the population (89.7%) , the Heterozygous (AC) was 10.3% but The (CC) homozygous mutants were not found in this study. Negative correlation between the dose of warfarin and the presence of variants in the studied SNPs.
Conclusion: CYP2C92 and CYP2C93 polymorphisms significantly influence warfarin dose requirements by reducing drug clearance. These findings support the use of pharmacogenetic testing to guide personalized warfarin therapy, improving dose accuracy and patient safety.
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