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CYP2D6 extensive, intermediate, and poor phenotypes and genotypes in a Polish population
P Niewinski1, K Orzechowska-Juzwenko, M Hurkacz
1Department of Clinical Pharmacology, Wroclaw Medical University, Poland. niewinski@kn.pl
European Journal of Clinical Pharmacology
|January 23, 2003
Summary
This study found that CYP2D6 genotype and phenotype frequencies are consistent in the Polish population. These findings align with other white populations, supporting accurate CYP2D6 genetic testing.
Area of Science:
- Pharmacogenomics
- Human Genetics
Background:
- The cytochrome P450 2D6 (CYP2D6) enzyme plays a crucial role in metabolizing numerous medications.
- Understanding CYP2D6 genetic and metabolic variations is essential for personalized medicine.
Purpose of the Study:
- To determine the distribution of CYP2D6 genotypes and phenotypes in a Polish population.
- To assess the concordance between CYP2D6 genotyping and phenotyping methods.
Main Methods:
- Genotyping and phenotyping of CYP2D6 in 600 healthy individuals from southwestern Poland.
- Phenotype analysis used sparteine as a model drug.
- Genotype analysis involved polymerase chain reaction and restriction fragment length polymorphism for key CYP2D6 alleles (*1, *3, *4).
Main Results:
- Prevalence of CYP2D6 poor metabolizers was 8.3% by phenotype and 8.0% by genotype.
- Allele frequencies were 75.7% for CYP2D6*1, 1.3% for CYP2D6*3, and 23.0% for CYP2D6*4.
- Good concordance was observed between CYP2D6 phenotype and genotype results in a subset of 60 individuals.
Conclusions:
- The frequencies of CYP2D6 poor metabolizers in the Polish population are consistent between genotype and phenotype analyses.
- These findings are comparable to those in other white populations.
- The study supports the reliability of CYP2D6 genetic testing for predicting metabolic status in this population.
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