Accurate determination of the CYP2D6 (*1/*4)xN genotype by quantitative PCR
-
Kirsten M. Pondman
,
Ron H.N. van Schaik
Abstract
Background:
CYP2D6 is responsible for the metabolism of approximately 25% of all drugs. The expression of cytochrome P450 2D6 (CYP2D6) is influenced by a combination of factors including polymorphisms in the CYP2D6 gene. Analysis of the CYP2D6 genotype is used to personalize the medication to a patient’s metabolism. Although many genotypes can be determined using standard genotype analysis, in some cases, an incomplete analysis is performed. The CYP2D6 genotype *1/*4 often occurs in combination with a multiplication of the CYP2D6 gene, and is reported as (*1/*4)xN. Accurate determination of the multiplied gene is essential to provide a phenotype prediction for these patients. Duplication of the *1 gene leads to an extensive metabolizer genotype whereas multiplication of the *4 gene would not lead to extra functional enzyme and therefore provides an intermediate metabolizer phenotype.
Methods:
Here, a technique is described in which the copy numbers of both the *4 and *1 genes are determined using quantitative PCR techniques.
Results and conclusions:
This technique provides a method to predict the patient’s CYP2D6 phenotype, and is therefore an important step toward personalized medicine.
Author contributions All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
Research funding: None declared.
Employment or leadership: None declared.
Honorarium: None declared.
Competing interests: The funding organization(s) played no role in the study design; in the collection, analysis, and interpretation of data; in the writing of the report; or in the decision to submit the report for publication.
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Articles in the same Issue
- Frontmatter
- Editorial
- Drug-drug interactions. Things to do in pain management
- Reviews
- Carboxylesterase 1 genes: systematic review and evaluation of existing genotyping procedures
- Metabolism and mechanisms of action of hyaluronan in human biology
- Original Articles
- Accurate determination of the CYP2D6 (*1/*4)xN genotype by quantitative PCR
- Effect of SLCO1B1 gene polymorphisms and vitamin D on statin-induced myopathy
- Effect of cilostazol on platelet reactivity among patients with peripheral artery disease on clopidogrel therapy
- Short Communication
- Preemptive NUDT15 genotyping: redefining the management of patients with thiopurine-induced toxicity
