title: Implementation of Cell Samples as Controls in National Proficiency Testing for Clopidogrel Therapy-Related CYP2C19 Genotyping in China: A Novel Approach.
abstract: Laboratories are increasingly requested to perform CYP2C19 genetic testing when managing clopidogrel therapy, especially in patients with acute coronary syndrome undergoing percutaneous coronary intervention. To ensure high quality molecular testing and ascertain that the referring clinician has the correct information for CYP2C19 genotype-directed antiplatelet therapy, a proficiency testing scheme was set up to evaluate the laboratory performance for the entire testing process. Proficiency panels of 10 cell samples encompassing the common CYP2C19 genetic polymorphisms were distributed to 62 participating laboratories for routine molecular testing and the responses were analyzed for accuracy of genotyping and the reporting of results. Data including the number of samples tested, the accreditation/certification status, and test methodology of each individual laboratory were also reviewed. Fifty-seven of the 62 participants correctly identified the CYP2C19 variants in all samples. There were six genotyping errors, with a corresponding analytical sensitivity of 98.5% (333/338 challenges; 95% confidence interval: 96.5-99.5%) and an analytic specificity of 99.6% (281/282; 95% confidence interval: 98.0-99.9%). Reports of the CYP2C19 genotyping results often lacked essential information. In conclusion, clinical laboratories demonstrated good analytical sensitivity and specificity; however, the pharmacogenetic testing community requires additional education regarding the correct reporting of CYP2C19 genetic test results.
authors.affiliation: National Center for Clinical Laboratories, Beijing Hospital, Beijing 100730, P R China.
authors.forename: Guigao
authors.initials: G
authors.lastname: Lin
authors.affiliation: National Center for Clinical Laboratories, Beijing Hospital, Beijing 100730, P R China; Graduate School, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing 100730, P R China.
authors.forename: Lang
authors.initials: L
authors.lastname: Yi
authors.affiliation: National Center for Clinical Laboratories, Beijing Hospital, Beijing 100730, P R China.
authors.forename: Kuo
authors.initials: K
authors.lastname: Zhang
authors.affiliation: National Center for Clinical Laboratories, Beijing Hospital, Beijing 100730, P R China.
authors.forename: Lunan
authors.initials: L
authors.lastname: Wang
authors.affiliation: National Center for Clinical Laboratories, Beijing Hospital, Beijing 100730, P R China.
authors.forename: Rui
authors.initials: R
authors.lastname: Zhang
authors.affiliation: National Center for Clinical Laboratories, Beijing Hospital, Beijing 100730, P R China.
authors.forename: Jiehong
authors.initials: J
authors.lastname: Xie
authors.affiliation: National Center for Clinical Laboratories, Beijing Hospital, Beijing 100730, P R China.
authors.forename: Jinming
authors.initials: J
authors.lastname: Li
mesh_terms: D054058:Acute Coronary Syndrome / Q000175:diagnosis / Q000188:drug therapy / Q000235:genetics*; D000483:Alleles; D002478:Cells, Cultured; D002681:China; D000077144:Clopidogrel; D065731:Cytochrome P-450 CYP2C19 / Q000235:genetics*; D005820:Genetic Testing / Q000379:methods; D005838:Genotype; D006284:Health Plan Implementation; D006801:Humans; D059021:Laboratory Proficiency Testing / Q000379:methods*; D062645:Percutaneous Coronary Intervention; D010597:Pharmacogenetics; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic / Q000235:genetics*; D013988:Ticlopidine / Q000031:analogs & derivatives* / Q000627:therapeutic use
chemical_list: D010975:Platelet Aggregation Inhibitors; D000077144:Clopidogrel; D065731:Cytochrome P-450 CYP2C19; D013988:Ticlopidine