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Reynolds KK, McNally BA, Linder MW. Clinical Utility and Economic Impact of CYP2D6 Genotyping. Clin Lab Med 2016; 36:525-42. [PMID: 27514466 DOI: 10.1016/j.cll.2016.05.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Pharmacogenetics examines an individual's genetic makeup to help predict the safety and efficacy of medications. Practical application optimizes treatment selection to decrease the failure rate of medications and improve clinical outcomes. Lack of efficacy is costly due to adverse drug reactions and increased hospital stays. Cytochrome P450 2D6 (CYP2D6) metabolizes roughly 25% of all drugs. Detecting variants that cause altered CYP2D6 enzymatic activity identifies patients at risk of adverse drug reactions or therapeutic failure with standard dosages of medications metabolized by CYP2D6. This article discusses the clinical application of pharmacogenetics to improve care and decrease costs.
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Affiliation(s)
- Kristen K Reynolds
- PGXL Laboratories, 201 East Jefferson Street, Suite 309, Louisville, KY 40202, USA; Department of Pathology and Laboratory Medicine, University of Louisville School of Medicine, 323 East Chestnut Street, Louisville, KY 40292, USA.
| | - Beth A McNally
- PGXL Laboratories, 201 East Jefferson Street, Suite 309, Louisville, KY 40202, USA
| | - Mark W Linder
- PGXL Laboratories, 201 East Jefferson Street, Suite 309, Louisville, KY 40202, USA; Department of Pathology and Laboratory Medicine, University of Louisville School of Medicine, 323 East Chestnut Street, Louisville, KY 40292, USA
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202
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Gentile G, Cipolla F, Capi M, Simmaco M, Lionetto L, Borro M. Precise medical decision making in geriatric anti-depressant therapy. EXPERT REVIEW OF PRECISION MEDICINE AND DRUG DEVELOPMENT 2016. [DOI: 10.1080/23808993.2016.1199951] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Giovanna Gentile
- Department of Neurosciences, Mental Health and Sensory Organs, Sapienza University of Rome, Rome, Italy
| | - Fabiola Cipolla
- Department of Neurosciences, Mental Health and Sensory Organs, Sapienza University of Rome, Rome, Italy
| | - Matilde Capi
- Department of Neurosciences, Mental Health and Sensory Organs, Sapienza University of Rome, Rome, Italy
| | - Maurizio Simmaco
- Department of Neurosciences, Mental Health and Sensory Organs, Sapienza University of Rome, Rome, Italy
| | - Luana Lionetto
- Advanced Molecular Diagnostics, IDI, Istituto Dermopatico dell’Immacolata-IRCCS, Rome, Italy
| | - Marina Borro
- Department of Neurosciences, Mental Health and Sensory Organs, Sapienza University of Rome, Rome, Italy
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203
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Advantages of Array-Based Technologies for Pre-Emptive Pharmacogenomics Testing. MICROARRAYS 2016; 5:microarrays5020012. [PMID: 27600079 PMCID: PMC5003488 DOI: 10.3390/microarrays5020012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 05/04/2016] [Accepted: 05/17/2016] [Indexed: 12/11/2022]
Abstract
As recognised by the National Institutes of Health (NIH) Precision Medicine Initiative (PMI), microarray technology currently provides a rapid, inexpensive means of identifying large numbers of known genomic variants or gene transcripts in experimental and clinical settings. However new generation sequencing techniques are now being introduced in many clinical genetic contexts, particularly where novel mutations are involved. While these methods can be valuable for screening a restricted set of genes for known or novel mutations, implementation of whole genome sequencing in clinical practice continues to present challenges. Even very accurate high-throughput methods with small error rates can generate large numbers of false negative or false positive errors due to the high numbers of simultaneous readings. Additional validation is likely to be required for safe use of any such methods in clinical settings. Custom-designed arrays can offer advantages for screening for common, known mutations and, in this context, may currently be better suited for accredited, quality-controlled clinical genetic screening services, as illustrated by their successful application in several large-scale pre-emptive pharmacogenomics programs now underway. Excessive, inappropriate use of next-generation sequencing may waste scarce research funds and other resources. Microarrays presently remain the technology of choice in applications that require fast, cost-effective genome-wide screening of variants of known importance, particularly for large sample sizes. This commentary considers some of the applications where microarrays continue to offer advantages over next-generation sequencing technologies.
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204
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Tajti J, Szok D, Majláth Z, Csáti A, Petrovics-Balog A, Vécsei L. Alleviation of pain in painful diabetic neuropathy. Expert Opin Drug Metab Toxicol 2016; 12:753-64. [PMID: 27149100 DOI: 10.1080/17425255.2016.1184648] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
INTRODUCTION Painful diabetic neuropathy (PDN) is a disabling pain condition. Its pathomechanism remains unknown, but a sensitization and neuronal hyperexcitabilty have been suggested. Only symptomatic pharmacological pain management treatment is currently available. AREAS COVERED The origin of PDN is enigmatic, and the evidence-based therapeutic guidelines therefore consist only of antidepressants and antiepileptics as first-line recommended drugs. This article relates to a MEDLINE/PubMed systematic search (2005-2015). EXPERT OPINION The results of the meta-analysis from the aspect of the efficacy of amitriptyline, duloxetine, venlafaxine, gabapentin and pregabalin are favorable, but the placebo response rate is relatively high in patients with neuropathic pain. For personalization of the medication of PDN patients, the optimum dosing, the genotyping of the metabolizing enzymes and optimum biomarkers are needed. As concerns the future perspectives, specific sodium channel subtype inhibitors acting on peripheral nociceptive neurons or modified T-type voltage-gated calcium channel blockers may be promising targets for pharmaceutical innovations. Another attractive strategy for the treatment is based on the effects of monoclonal antibodies against nerve growth factor, sodium channels, specific receptor and cytokines. Botulinum toxin A, capsaicin patch and spinal cord stimulation therapies are the nearest future therapeutic options for the treatment of PDN patients.
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Affiliation(s)
- János Tajti
- a Department of Neurology, Faculty of Medicine , University of Szeged , Szeged , Hungary
| | - Délia Szok
- a Department of Neurology, Faculty of Medicine , University of Szeged , Szeged , Hungary
| | - Zsófia Majláth
- a Department of Neurology, Faculty of Medicine , University of Szeged , Szeged , Hungary
| | - Anett Csáti
- a Department of Neurology, Faculty of Medicine , University of Szeged , Szeged , Hungary
| | - Anna Petrovics-Balog
- a Department of Neurology, Faculty of Medicine , University of Szeged , Szeged , Hungary
| | - László Vécsei
- a Department of Neurology, Faculty of Medicine , University of Szeged , Szeged , Hungary.,b MTA - SZTE Neuroscience Research Group , Szeged , Hungary
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205
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Pietarinen P, Tornio A, Niemi M. High Frequency ofCYP2D6Ultrarapid Metabolizer Genotype in the Finnish Population. Basic Clin Pharmacol Toxicol 2016; 119:291-6. [DOI: 10.1111/bcpt.12590] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2016] [Accepted: 03/17/2016] [Indexed: 11/27/2022]
Affiliation(s)
- Paavo Pietarinen
- Department of Clinical Pharmacology; University of Helsinki and Helsinki University Hospital; Helsinki Finland
| | - Aleksi Tornio
- Department of Clinical Pharmacology; University of Helsinki and Helsinki University Hospital; Helsinki Finland
| | - Mikko Niemi
- Department of Clinical Pharmacology; University of Helsinki and Helsinki University Hospital; Helsinki Finland
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206
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Smith TR, Kearney E, Hulick PJ, Kisor DF. History repeats itself: the family medication history and pharmacogenomics. Pharmacogenomics 2016; 17:669-78. [PMID: 27143300 DOI: 10.2217/pgs-2015-0015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Related to many drug gene-product interactions, application of pharmacogenomics can lead to improved medication efficacy while decreasing or avoiding adverse drug reactions. However, utilizing pharmacogenomics without other information does not allow for optimal medication therapy. Currently, there is a lack of documentation of family medication history, in other words, inefficacy and adverse reactions across family members throughout generations. The family medication history can serve as an impetus for pharmacogenomic testing to explain lack of medication efficacy or an adverse drug reaction and pre-emptive testing can drive recognition and documentation of medication response in family members. We propose combining the family medication history via pedigree construction with pharmacogenomics to further optimize medication therapy. We encourage clinicians to combine family medication history with pharmacogenomics.
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Affiliation(s)
- Thomas R Smith
- Manchester University Pharmacy Program, College of Pharmacy, Natural & Health Sciences, Fort Wayne, IN 46845, USA
| | | | - Peter J Hulick
- Division of Medical Genetics, NorthShore Research Institute, University of Chicago Pritzker School of Medicine, Chicago, IL 60201, USA
| | - David F Kisor
- Department of Pharmaceutical Sciences, Manchester University Pharmacy Program, Manchester University Pharmacogenomics Program, College of Pharmacy, Natural & Health Sciences, Fort Wayne, IN 46845, USA
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207
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McGrane IR, Loveland JG. Pharmacogenetics of Cytochrome P450 Enzymes in American Indian and Caucasian Children Admitted to a Psychiatric Hospital. J Child Adolesc Psychopharmacol 2016; 26:395-9. [PMID: 26871369 DOI: 10.1089/cap.2015.0180] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
OBJECTIVE The cytochrome P450 (CYP450) enzyme system metabolizes many psychiatric medications. We compare frequencies of alleles and phenotypes for CYP2D6, CYP2C9, and CYP2C19 in American Indian (AI) and Caucasian youth treated at a psychiatric hospital in the Northwestern United States. METHODS A retrospective chart review evaluated CYP450 pharmacogenetic (PGx) data from the Shodair Children's Hospital Clinical Genetic Laboratory between 2006 and 2014. CYP2D6 genotyping was performed using the xTAG® CYP2D6 Kit (Luminex, Austin, TX). CYP2C9 and CYP2C19 genotyping was performed by laboratory-developed assays using allele-specific quantitative polymerase chain reaction (qPCR) and/or melt-curve analysis. RESULTS A total of 123 AIs and 688 Caucasians met criteria for inclusion. The overall prevalence of CYP2D6 poor metabolizers was 8.3% (95% Confidence Interval [CI] 6.1%, 10.4%), 9.3% in Caucasians (95% CI 7.1%, 11.5%), and 2.4% in AIs (95% CI 0%, 5.2%). The overall prevalence of CYP2D6 ultrarapid metabolizers was 1.6% (95% CI 0.7%, 2.5%), 1.6% in the Caucasians (95% CI 0.7%, 2.5%), and 1.6% in AIs (95% CI 0%, 3.9%). The overall prevalence of CYP2C9 poor metabolizers was 3% (95% CI 1.7%, 4.2%), 3.2% in Caucasians (95% CI 1.8%, 4.6%), and 1.8% in AIs (95% CI 0%, 4.2%). The overall prevalence of CYP2C19 poor metabolizers was 2.5% (95% CI 1.3%, 3.6%), 2.9% in Caucasians (95% CI 1.6%, 4.2%), and 0% in AIs. The overall prevalence of CYP2C19 ultrarapid metabolizers was 1.5% (95% CI 0.6%, 2.4%), 1.6% in Caucasians (95% CI 0.6%, 2.6%), and 0.9% in AIs (95% CI 0%, 2.6%). CONCLUSIONS This study is the first to identify differences in polymorphism frequencies of the CYP450 system in AIs and Caucasian youth admitted to a psychiatric hospital. Our findings warrant further study of these populations to determine if these differences are generalizable to the larger population of Caucasian and AI/Alaska Native youth in the Northwestern United States.
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Affiliation(s)
- Ian R McGrane
- Department of Pharmacy, Shodair Children's Hospital , Helena, Montana
| | - Joshua G Loveland
- Department of Pharmacy, Shodair Children's Hospital , Helena, Montana
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208
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Oberg V, Differding J, Fisher M, Hines L, Wilke RA. Navigating pleiotropy in precision medicine: pharmacogenes from trauma to behavioral health. Pharmacogenomics 2016; 17:499-505. [PMID: 27023676 DOI: 10.2217/pgs.16.6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A strong emerging principle in the field of precision medicine is that variation in any one pharmacogene may impact clinical outcome for more than one drug. Variants tested in the acute care setting often have downstream implications for other drugs impacting chronic disease management. A flexible framework is needed as clinicians and scientists move toward deploying automated decision support for gene-based drug dosing in electronic medical records.
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Affiliation(s)
- Vicki Oberg
- Department of Clinical Research, Sanford Healthcare-Fargo, 801 North Broadway, Fargo, ND 58102, USA
| | - Jerome Differding
- Department of Trauma and Surgical Critical Care, Sanford Healthcare-Fargo, 801 North Broadway, Fargo, ND 5810, USA
| | - Morgan Fisher
- Department of Medical Genetics, Sanford Healthcare-Fargo, 801 North Broadway, Fargo, ND 58102, USA
| | - Lindsay Hines
- Department of Clinical Psychology, University of North Dakota, 700 South 1st Avenue, Fargo, ND 58103, USA
| | - Russell A Wilke
- Department of Internal Medicine, University of South Dakota Sanford School of Medicine, 1400 West 22nd Street, Sioux Falls, SD 57105, USA
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209
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Hall JL, Ryan JJ, Bray BE, Brown C, Lanfear D, Newby LK, Relling MV, Risch NJ, Roden DM, Shaw SY, Tcheng JE, Tenenbaum J, Wang TN, Weintraub WS. Merging Electronic Health Record Data and Genomics for Cardiovascular Research: A Science Advisory From the American Heart Association. ACTA ACUST UNITED AC 2016; 9:193-202. [PMID: 26976545 DOI: 10.1161/hcg.0000000000000029] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The process of scientific discovery is rapidly evolving. The funding climate has influenced a favorable shift in scientific discovery toward the use of existing resources such as the electronic health record. The electronic health record enables long-term outlooks on human health and disease, in conjunction with multidimensional phenotypes that include laboratory data, images, vital signs, and other clinical information. Initial work has confirmed the utility of the electronic health record for understanding mechanisms and patterns of variability in disease susceptibility, disease evolution, and drug responses. The addition of biobanks and genomic data to the information contained in the electronic health record has been demonstrated. The purpose of this statement is to discuss the current challenges in and the potential for merging electronic health record data and genomics for cardiovascular research.
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210
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Steuer AE, Schmidhauser C, Tingelhoff EH, Schmid Y, Rickli A, Kraemer T, Liechti ME. Impact of Cytochrome P450 2D6 Function on the Chiral Blood Plasma Pharmacokinetics of 3,4-Methylenedioxymethamphetamine (MDMA) and Its Phase I and II Metabolites in Humans. PLoS One 2016; 11:e0150955. [PMID: 26967321 PMCID: PMC4788153 DOI: 10.1371/journal.pone.0150955] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Accepted: 02/22/2016] [Indexed: 12/05/2022] Open
Abstract
3,4-methylenedioxymethamphetamine (MDMA; ecstasy) metabolism is known to be stereoselective, with preference for S-stereoisomers. Its major metabolic step involves CYP2D6-catalyzed demethylenation to 3,4-dihydroxymethamphetamine (DHMA), followed by methylation and conjugation. Alterations in CYP2D6 genotype and/or phenotype have been associated with higher toxicity. Therefore, the impact of CYP2D6 function on the plasma pharmacokinetics of MDMA and its phase I and II metabolites was tested by comparing extensive metabolizers (EMs), intermediate metabolizers (IMs), and EMs that were pretreated with bupropion as a metabolic inhibitor in a controlled MDMA administration study. Blood plasma samples were collected from 16 healthy participants (13 EMs and three IMs) up to 24 h after MDMA administration in a double-blind, placebo-controlled, four-period, cross-over design, with subjects receiving 1 week placebo or bupropion pretreatment followed by a single placebo or MDMA (125 mg) dose. Bupropion pretreatment increased the maximum plasma concentration (Cmax) and area under the plasma concentration-time curve from 0 to 24 h (AUC24) of R-MDMA (9% and 25%, respectively) and S-MDMA (16% and 38%, respectively). Bupropion reduced the Cmax and AUC24 of the CYP2D6-dependently formed metabolite stereoisomers of DHMA 3-sulfate, DHMA 4-sulfate, and 4-hydroxy-3-methoxymethamphetamine (HMMA sulfate and HMMA glucuronide) by approximately 40%. The changes that were observed in IMs were generally comparable to bupropion-pretreated EMs. Although changes in stereoselectivity based on CYP2D6 activity were observed, these likely have low clinical relevance. Bupropion and hydroxybupropion stereoisomer pharmacokinetics were unaltered by MDMA co-administration. The present data might aid further interpretations of toxicity based on CYP2D6-dependent MDMA metabolism.
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Affiliation(s)
- Andrea E. Steuer
- Department of Forensic Pharmacology & Toxicology, Zurich Institute of Forensic Medicine, University of Zurich, Zurich, Switzerland
- * E-mail:
| | - Corina Schmidhauser
- Department of Forensic Pharmacology & Toxicology, Zurich Institute of Forensic Medicine, University of Zurich, Zurich, Switzerland
| | - Eva H. Tingelhoff
- Department of Forensic Pharmacology & Toxicology, Zurich Institute of Forensic Medicine, University of Zurich, Zurich, Switzerland
| | - Yasmin Schmid
- Psychopharmacology Research, Division of Clinical Pharmacology and Toxicology, Department of Biomedicine and Department of Clinical Research, University Hospital Basel, Basel, Switzerland
| | - Anna Rickli
- Psychopharmacology Research, Division of Clinical Pharmacology and Toxicology, Department of Biomedicine and Department of Clinical Research, University Hospital Basel, Basel, Switzerland
| | - Thomas Kraemer
- Department of Forensic Pharmacology & Toxicology, Zurich Institute of Forensic Medicine, University of Zurich, Zurich, Switzerland
| | - Matthias E. Liechti
- Psychopharmacology Research, Division of Clinical Pharmacology and Toxicology, Department of Biomedicine and Department of Clinical Research, University Hospital Basel, Basel, Switzerland
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211
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Abstract
The study of pharmacogenomics is rapidly growing, particularly in the field of mental health. Understanding pharmacogenomic principles can be a challenge for many clinicians. Most mental health genomic data concentrates on variability (response, side effects) with antidepressants and atypical antipsychotics. Current pharmacogenomic practice and research primarily focuses on two areas: pharmacodynamics and pharmacokinetics. Based on the current literature, genetic polymorphisms of pharmacodynamics and pharmacokinetics parameters likely influence medication efficacy, therefore affecting the therapeutic benefit. Additionally, certain pharmacodynamic and pharmacokinetic polymorphisms have been linked to an elevated risk of side effects and adverse events with these medications. In this review, specific pharmacodynamic and pharmacokinetic polymorphisms related to antidepressants and atypical antipsychotics will be discussed, as well as the potential clinical effect these genomic abnormalities have within psychiatric care.
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Affiliation(s)
- Jonathan F Lister
- PGY2 Psychiatric Pharmacy Resident, Veterans Affairs Tennessee Valley Healthcare System, Murfreesboro, Tennessee,
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212
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Ji Y, Skierka JM, Blommel JH, Moore BE, VanCuyk DL, Bruflat JK, Peterson LM, Veldhuizen TL, Fadra N, Peterson SE, Lagerstedt SA, Train LJ, Baudhuin LM, Klee EW, Ferber MJ, Bielinski SJ, Caraballo PJ, Weinshilboum RM, Black JL. Preemptive Pharmacogenomic Testing for Precision Medicine: A Comprehensive Analysis of Five Actionable Pharmacogenomic Genes Using Next-Generation DNA Sequencing and a Customized CYP2D6 Genotyping Cascade. J Mol Diagn 2016; 18:438-445. [PMID: 26947514 DOI: 10.1016/j.jmoldx.2016.01.003] [Citation(s) in RCA: 144] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Revised: 12/24/2015] [Accepted: 01/11/2016] [Indexed: 01/08/2023] Open
Abstract
Significant barriers, such as lack of professional guidelines, specialized training for interpretation of pharmacogenomics (PGx) data, and insufficient evidence to support clinical utility, prevent preemptive PGx testing from being widely clinically implemented. The current study, as a pilot project for the Right Drug, Right Dose, Right Time-Using Genomic Data to Individualize Treatment Protocol, was designed to evaluate the impact of preemptive PGx and to optimize the workflow in the clinic setting. We used an 84-gene next-generation sequencing panel that included SLCO1B1, CYP2C19, CYP2C9, and VKORC1 together with a custom-designed CYP2D6 testing cascade to genotype the 1013 subjects in laboratories approved by the Clinical Laboratory Improvement Act. Actionable PGx variants were placed in patient's electronic medical records where integrated clinical decision support rules alert providers when a relevant medication is ordered. The fraction of this cohort carrying actionable PGx variant(s) in individual genes ranged from 30% (SLCO1B1) to 79% (CYP2D6). When considering all five genes together, 99% of the subjects carried an actionable PGx variant(s) in at least one gene. Our study provides evidence in favor of preemptive PGx testing by identifying the risk of a variant being present in the population we studied.
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Affiliation(s)
- Yuan Ji
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Jennifer M Skierka
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Joseph H Blommel
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Brenda E Moore
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Douglas L VanCuyk
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Jamie K Bruflat
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Lisa M Peterson
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | | | - Numrah Fadra
- Department of Health Sciences Research, Mayo Clinic, Rochester, Minnesota
| | - Sandra E Peterson
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Susan A Lagerstedt
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Laura J Train
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Linnea M Baudhuin
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
| | - Eric W Klee
- Department of Health Sciences Research, Mayo Clinic, Rochester, Minnesota; Center for Individualized Medicine, Mayo Clinic, Rochester, Minnesota
| | - Matthew J Ferber
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota; Center for Individualized Medicine, Mayo Clinic, Rochester, Minnesota
| | | | - Pedro J Caraballo
- Department of General Internal Medicine, Mayo Clinic, Rochester, Minnesota
| | - Richard M Weinshilboum
- Center for Individualized Medicine, Mayo Clinic, Rochester, Minnesota; Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, Minnesota
| | - John L Black
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota.
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213
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Abstract
Adverse drug reactions (ADRs) are a major public health concern and cause significant patient morbidity and mortality. Pharmacogenomics is the study of how genetic polymorphisms affect an individual's response to pharmacotherapy at the level of a whole genome. This article updates our knowledge on how genetic polymorphisms of important genes alter the risk of ADR occurrence after an extensive literature search. To date, at least 244 pharmacogenes identified have been associated with ADRs of 176 clinically used drugs based on PharmGKB. At least 28 genes associated with the risk of ADRs have been listed by the Food and Drug Administration as pharmacogenomic biomarkers. With the availability of affordable and reliable testing tools, pharmacogenomics looks promising to predict, reduce, and minimize ADRs in selected populations.
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214
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Andersen RL, Johnson DJ, Patel JN. Personalizing supportive care in oncology patients using pharmacogenetic-driven treatment pathways. Pharmacogenomics 2016; 17:417-34. [PMID: 26871520 DOI: 10.2217/pgs.15.178] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Cancer patients frequently suffer from disease- and treatment-related pain, nausea and depression, which severely reduces patients' quality of life. It is critical that clinicians are aware of drug-gene interactions and recognize the utility of applying pharmacogenetic information to personalize and improve supportive care. Pharmacogenetic-based algorithms may enhance clinical outcomes by allowing the clinician to select the 'least genetically vulnerable' drug. This review summarizes clinically relevant drug-gene interactions and presents pharmacogenetic-driven treatment pathways for depression, nausea/vomiting and pain. Ideally, this review provides a resource for clinicians to consult when selecting pharmacotherapy for a patient who presents with limited pharmacogenetic test results, with the hope of better controlling burdensome symptoms and improving the quality of life for cancer patients.
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Affiliation(s)
- Rebecca L Andersen
- Wingate University School of Pharmacy, 515 N Main St, Wingate, NC 28174, USA
| | - Daniel J Johnson
- University of North Carolina Eshelman School of Pharmacy, CB #7355, Chapel Hill, NC 27599, USA
| | - Jai N Patel
- University of North Carolina Eshelman School of Pharmacy, CB #7355, Chapel Hill, NC 27599, USA.,Levine Cancer Institute, Carolinas HealthCare System, 1021 Morehead Medical Drive, Charlotte, NC 28204, USA
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215
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Vanwong N, Ngamsamut N, Hongkaew Y, Nuntamool N, Puangpetch A, Chamnanphon M, Sinrachatanant A, Limsila P, Sukasem C. Detection of CYP2D6 polymorphism using Luminex xTAG technology in autism spectrum disorder: CYP2D6 activity score and its association with risperidone levels. Drug Metab Pharmacokinet 2016; 31:156-62. [PMID: 26944100 DOI: 10.1016/j.dmpk.2016.01.005] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 01/25/2016] [Accepted: 01/28/2016] [Indexed: 11/19/2022]
Abstract
CYP2D6 is involved in the biotransformation of a large number of drugs, including risperidone. This study was designed to detect CYP2D6 polymorphisms with a Luminex assay, including assessment the relationship of CYP2D6 polymorphisms and risperidone plasma concentration in autism spectrum disorder children (ASD) treated with risperidone. All 84 ASD patients included in this study had been receiving risperidone at least for 1 month. The CYP2D6 genotypes were determined by Luminex assay. Plasma concentrations of risperidone and 9-hydroxyrisperidone were measured using LC/MS/MS. Among the 84 patients, there were 46 (55.42%) classified as EM, 33 (39.76%) as IM, and 4(4.82%) as UM. The plasma concentration of risperidone and risperidone/9-hydroxyrisperidone ratio in the patients were significant differences among the CYP2D6 predicted phenotype group (P = 0.001 and P < 0.0001 respectively). Moreover, the plasma concentration of risperidone and risperidone/9-hydroxyrisperidone ratio in the patients with CYP2D6 activity score 0.5 were significantly higher than those with the CYP2D6 activity score 2.0 (P = 0.004 and P = 0.002 respectively). These findings suggested that the determination of the accurate CYP2D6 genotype-predicted phenotype is essential in the clinical setting and individualization of drug therapy. The use of the Luminex assay for detection of CYP2D6 polymorphisms could help us more accurately identify an individual's CYP2D6 phenotype.
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Affiliation(s)
- Natchaya Vanwong
- Division of Pharmacogenomics and Personalized Medicine, Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok 10400, Thailand; Laboratory for Pharmacogenomics, Somdech Phra Debaratana Medical Center (SDMC), Ramathibodi Hospital, Bangkok, Thailand
| | - Nattawat Ngamsamut
- Yuwaprasart Waithayopathum Child and Adolescent Psychiatric Hospital, Department of Mental Health Services, Ministry of Public Health, Thailand
| | - Yaowaluck Hongkaew
- Division of Pharmacogenomics and Personalized Medicine, Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok 10400, Thailand; Laboratory for Pharmacogenomics, Somdech Phra Debaratana Medical Center (SDMC), Ramathibodi Hospital, Bangkok, Thailand
| | - Nopphadol Nuntamool
- Division of Pharmacogenomics and Personalized Medicine, Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok 10400, Thailand; Laboratory for Pharmacogenomics, Somdech Phra Debaratana Medical Center (SDMC), Ramathibodi Hospital, Bangkok, Thailand; Molecular Medicine, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Apichaya Puangpetch
- Division of Pharmacogenomics and Personalized Medicine, Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok 10400, Thailand; Laboratory for Pharmacogenomics, Somdech Phra Debaratana Medical Center (SDMC), Ramathibodi Hospital, Bangkok, Thailand
| | - Montri Chamnanphon
- Division of Pharmacogenomics and Personalized Medicine, Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok 10400, Thailand; Laboratory for Pharmacogenomics, Somdech Phra Debaratana Medical Center (SDMC), Ramathibodi Hospital, Bangkok, Thailand
| | - Ananya Sinrachatanant
- Yuwaprasart Waithayopathum Child and Adolescent Psychiatric Hospital, Department of Mental Health Services, Ministry of Public Health, Thailand
| | - Penkhae Limsila
- Yuwaprasart Waithayopathum Child and Adolescent Psychiatric Hospital, Department of Mental Health Services, Ministry of Public Health, Thailand
| | - Chonlaphat Sukasem
- Division of Pharmacogenomics and Personalized Medicine, Department of Pathology, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok 10400, Thailand; Laboratory for Pharmacogenomics, Somdech Phra Debaratana Medical Center (SDMC), Ramathibodi Hospital, Bangkok, Thailand.
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Sánchez-Iglesias S, García-Solaesa V, García-Berrocal B, Sanchez-Martín A, Lorenzo-Romo C, Martín-Pinto T, Gaedigk A, González-Buitrago JM, Isidoro-García M. Role of Pharmacogenetics in Improving the Safety of Psychiatric Care by Predicting the Potential Risks of Mania in CYP2D6 Poor Metabolizers Diagnosed With Bipolar Disorder. Medicine (Baltimore) 2016; 95:e2473. [PMID: 26871771 PMCID: PMC4753865 DOI: 10.1097/md.0000000000002473] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
One of the main concerns in psychiatric care is safety related to drug management. Pharmacogenetics provides an important tool to assess causes that may have contributed the adverse events during psychiatric therapy. This study illustrates the potential of pharmacogenetics to identify those patients for which pharmacogenetic-guided therapy could be appropriate. It aimed to investigate CYP2D6 genotype in our psychiatric population to assess the value of introducing pharmacogenetics as a primary improvement for predicting side effects.A broad series of 224 psychiatric patients comprising psychotic disorders, depressive disturbances, bipolar disorders, and anxiety disorders was included. The patients were genotyped with the AmpliChip CYP450 Test to analyzing 33 allelic variants of the CYP2D6 gene.All bipolar patients with poor metabolizer status showed maniac switching when CYP2D6 substrates such as selective serotonin reuptake inhibitors were prescribed. No specific patterns were identified for adverse events for other disorders.We propose to utilize pharmacogenetic testing as an intervention to aid in the identification of patients who are at risk of developing affective switching in bipolar disorder treated with selective serotonin reuptake inhibitors, CYP2D6 substrates, and inhibitors.
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Affiliation(s)
- Santiago Sánchez-Iglesias
- From the Servicio de Psiquiatría, Hospital Universitario de Salamanca (SS-I, CL-R, TM-P); Instituto Biosanitario de Salamanca, IBSAL (VG-S, BG-B, AS-M, JML-R, MI-G); Servicio de Bioquímica Clínica, Hospital Universitario de Salamanca (BG-B, JMG-B, MI-G); Servicio de Farmacia, Hospital Universitario de Salamanca, Spain (AS-M); Division of Clinical Pharmacology, Toxicology and Therapeutic Innovation, Children's Mercy Hospital (AG); Department of Pediatrics, School of Medicine, University of Missouri-Kansas City, Kansas City, MO, USA (AG); and Departamento de Medicina, Universidad de Salamanca, Spain (MI-G)
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Balwani M, Burrow TA, Charrow J, Goker-Alpan O, Kaplan P, Kishnani PS, Mistry P, Ruskin J, Weinreb N. Recommendations for the use of eliglustat in the treatment of adults with Gaucher disease type 1 in the United States. Mol Genet Metab 2016; 117:95-103. [PMID: 26387627 DOI: 10.1016/j.ymgme.2015.09.002] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 09/01/2015] [Accepted: 09/01/2015] [Indexed: 12/30/2022]
Abstract
In Gaucher disease, deficient activity of acid β-glucosidase results in accumulation of its substrates, glucosylceramide and glucosylsphingosine, within the lysosomes of cells primarily in the spleen, liver, bone marrow, and occasionally the lung. The multisystem disease is predominantly characterized by hepatosplenomegaly, anemia, thrombocytopenia, and skeletal disease. Enzyme replacement therapy with recombinant human acid β-glucosidase has been the first-line therapy for Gaucher disease type 1 for more than two decades. Eliglustat, a novel oral substrate reduction therapy, was recently approved in the United States and the European Union as a first-line treatment for adults with Gaucher disease type 1. Eliglustat inhibits glucosylceramide synthase, thereby decreasing production of the substrate glucosylceramide and reducing its accumulation. Although existing recommendations for the care of patients with Gaucher disease remain in effect, unique characteristics of eliglustat require additional investigation and monitoring. A panel of physicians with expertise in Gaucher disease and experience with eliglustat in the clinical trials provide guidance regarding the use of eliglustat, including considerations before starting therapy and monitoring of patients on eliglustat therapy.
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Affiliation(s)
- Manisha Balwani
- Department of Genetics and Genomic Sciences, One Gustave L. Levy Place, Box 1497, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
| | - Thomas Andrew Burrow
- Cincinnati Children's Hospital Medical Center, Division of Human Genetics, 3333 Burnet Avenue, MLC 4006, Cincinnati, OH 45229, USA.
| | - Joel Charrow
- Department of Pediatrics, Northwestern University Feinberg School of Medicine, Division of Genetics, Birth Defects and Metabolism, Ann and Robert H. Lurie Children's Hospital of Chicago, 225 East Chicago Avenue, Chicago, IL 60611, USA.
| | - Ozlem Goker-Alpan
- Lysosomal Disorders Unit, O&O Alpan, LLC, 11212 Waples Mill Road, Fairfax, VA 22030, USA.
| | - Paige Kaplan
- Lysosomal Center, Division of Genetics, Children's Hospital of Philadelphia, Civic Center Blvd, Philadelphia, PA 19104, USA.
| | - Priya S Kishnani
- Duke University School of Medicine, Department of Pediatrics, DUMC 103856, 595 Lasalle Street, GSRB 1, 4th Floor, Room 4010, Durham, NC 27710, USA.
| | - Pramod Mistry
- Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA.
| | - Jeremy Ruskin
- Massachusetts General Hospital, Electrophysiology Lab/Arrhythmia Service, 55 Fruit Street, Boston, MA 02114-2696, USA.
| | - Neal Weinreb
- University Research Foundation for Lysosomal Storage Diseases, Inc., 7367 Wexford Terrace, Boca Raton, FL 33433, USA.
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218
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Could Adult European Pharmacoresistant Epilepsy Patients Be Treated With Higher Doses of Zonisamide? Clin Neuropharmacol 2016; 39:121-4. [PMID: 26818046 DOI: 10.1097/wnf.0000000000000138] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To examine the clinical effect (efficacy and tolerability) of high doses of zonisamide (ZNS) (>500 mg/d) in adult patients with pharmacoresistant epilepsy. METHODS Between 2006 and 2013, all epileptic outpatients treated with high doses of ZNS were selected. Safety and efficacy were assessed based on patient and caregiver reports. Serum levels of ZNS and other concomitant antiepileptic drugs were evaluated if available. RESULTS Nine patients (5 female): 8 focal/1 generalized pharmacoresistant epilepsy. Mean age: 34 years. Most frequent seizure type: complex partial seizures; other seizure types: generalized tonic-clonic, tonic, myoclonia. Zonisamide in polytherapy in all (100%), administered in tritherapy in 3 (33%) of 9 patients; mean dose: 633 (600-700) mg/d; efficacy (>50% seizure reduction) was observed in 5 (55%) of 9 patients. Five of 9 patients are still taking high doses of ZNS (more than 1 year). Adverse events were observed in 3 (37%) of 8 patients. Good tolerance to high doses of other antiepileptic drugs had been observed in 6 (66%) of 9 patients. Plasma levels of ZNS were only available in 2 patients; both were in the therapeutic range (34.95, 30.91) (10-40 mg/L). CONCLUSIONS High doses of ZNS are effective and safe in pharmacoresistant epileptic patients. Therapeutic drug monitoring of ZNS may be considered at therapeutic failure.
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Constellation: a tool for rapid, automated phenotype assignment of a highly polymorphic pharmacogene, CYP2D6, from whole-genome sequences. NPJ Genom Med 2016; 1:15007. [PMID: 29263805 PMCID: PMC5685293 DOI: 10.1038/npjgenmed.2015.7] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 11/10/2015] [Accepted: 11/10/2015] [Indexed: 12/30/2022] Open
Abstract
An important component of precision medicine-the use of whole-genome sequencing (WGS) to guide lifelong healthcare-is electronic decision support to inform drug choice and dosing. To achieve this, automated identification of genetic variation in genes involved in drug absorption, distribution, metabolism, excretion and response (ADMER) is required. CYP2D6 is a major enzyme for drug bioactivation and elimination. CYP2D6 activity is predominantly governed by genetic variation; however, it is technically arduous to haplotype. Not only is the nucleotide sequence of CYP2D6 highly polymorphic, but the locus also features diverse structural variations, including gene deletion, duplication, multiplication events and rearrangements with the nonfunctional, neighbouring CYP2D7 and CYP2D8 genes. We developed Constellation, a probabilistic scoring system, enabling automated ascertainment of CYP2D6 activity scores from 2×100 paired-end WGS. The consensus reference method included TaqMan genotyping assays, quantitative copy-number variation determination and Sanger sequencing. When compared with the consensus reference Constellation had an analytic sensitivity of 97% (59 of 61 diplotypes) and analytic specificity of 95% (116 of 122 haplotypes). All extreme phenotypes, i.e., poor and ultrarapid metabolisers were accurately identified by Constellation. Constellation is anticipated to be extensible to functional variation in all ADMER genes, and to be performed at marginal incremental financial and computational costs in the setting of diagnostic WGS.
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Riffel AK, Dehghani M, Hartshorne T, Floyd KC, Leeder JS, Rosenblatt KP, Gaedigk A. CYP2D7 Sequence Variation Interferes with TaqMan CYP2D6 (*) 15 and (*) 35 Genotyping. Front Pharmacol 2016; 6:312. [PMID: 26793106 PMCID: PMC4709848 DOI: 10.3389/fphar.2015.00312] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 12/17/2015] [Indexed: 12/14/2022] Open
Abstract
TaqMan™ genotyping assays are widely used to genotype CYP2D6, which encodes a major drug metabolizing enzyme. Assay design for CYP2D6 can be challenging owing to the presence of two pseudogenes, CYP2D7 and CYP2D8, structural and copy number variation and numerous single nucleotide polymorphisms (SNPs) some of which reflect the wild-type sequence of the CYP2D7 pseudogene. The aim of this study was to identify the mechanism causing false-positive CYP2D6*15 calls and remediate those by redesigning and validating alternative TaqMan genotype assays. Among 13,866 DNA samples genotyped by the CompanionDx® lab on the OpenArray platform, 70 samples were identified as heterozygotes for 137Tins, the key SNP of CYP2D6*15. However, only 15 samples were confirmed when tested with the Luminex xTAG CYP2D6 Kit and sequencing of CYP2D6-specific long range (XL)-PCR products. Genotype and gene resequencing of CYP2D6 and CYP2D7-specific XL-PCR products revealed a CC>GT dinucleotide SNP in exon 1 of CYP2D7 that reverts the sequence to CYP2D6 and allows a TaqMan assay PCR primer to bind. Because CYP2D7 also carries a Tins, a false-positive mutation signal is generated. This CYP2D7 SNP was also responsible for generating false-positive signals for rs769258 (CYP2D6*35) which is also located in exon 1. Although alternative CYP2D6*15 and *35 assays resolved the issue, we discovered a novel CYP2D6*15 subvariant in one sample that carries additional SNPs preventing detection with the alternate assay. The frequency of CYP2D6*15 was 0.1% in this ethnically diverse U.S. population sample. In addition, we also discovered linkage between the CYP2D7 CC>GT dinucleotide SNP and the 77G>A (rs28371696) SNP of CYP2D6*43. The frequency of this tentatively functional allele was 0.2%. Taken together, these findings emphasize that regardless of how careful genotyping assays are designed and evaluated before being commercially marketed, rare or unknown SNPs underneath primer and/or probe regions can impact the performance of PCR-based genotype assays, including TaqMan. Regardless of the test platform used, it is prudent to confirm rare allele calls by an independent method.
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Affiliation(s)
- Amanda K Riffel
- Division of Clinical Pharmacology, Toxicology and Therapeutic Innovation, Children's Mercy Kansas City Kansas City, MO, USA
| | - Mehdi Dehghani
- CompanionDx® Reference LabHouston, TX, USA; Division of Oncology, Department of Internal Medicine, University of Texas Health Science Center at HoustonHouston, TX, USA
| | - Toinette Hartshorne
- Genetic Analysis, Genetic Sciences Division, Thermo Fisher Scientific South San Francisco, CA, USA
| | | | - J Steven Leeder
- Division of Clinical Pharmacology, Toxicology and Therapeutic Innovation, Children's Mercy Kansas CityKansas City, MO, USA; School of Medicine, University of Missouri-Kansas CityKansas City, MO, USA
| | - Kevin P Rosenblatt
- CompanionDx® Reference LabHouston, TX, USA; Division of Oncology, Department of Internal Medicine, University of Texas Health Science Center at HoustonHouston, TX, USA
| | - Andrea Gaedigk
- Division of Clinical Pharmacology, Toxicology and Therapeutic Innovation, Children's Mercy Kansas CityKansas City, MO, USA; School of Medicine, University of Missouri-Kansas CityKansas City, MO, USA
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Brixner D, Biltaji E, Bress A, Unni S, Ye X, Mamiya T, Ashcraft K, Biskupiak J. The effect of pharmacogenetic profiling with a clinical decision support tool on healthcare resource utilization and estimated costs in the elderly exposed to polypharmacy. J Med Econ 2016; 19:213-28. [PMID: 26478982 DOI: 10.3111/13696998.2015.1110160] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE To compare healthcare resource utilization (HRU) and clinical decision-making for elderly patients based on cytochrome P450 (CYP) pharmacogenetic testing and the use of a comprehensive medication management clinical decision support tool (CDST), to a cohort of similar non-tested patients. METHODS An observational study compared a prospective cohort of patients ≥65 years subjected to pharmacogenetic testing to a propensity score (PS) matched historical cohort of untested patients in a claims database. Patients had a prescribed medication or dose change of at least one of 61 oral drugs or combinations of ≥3 drugs at enrollment. Four-month HRU outcomes examined included hospitalizations, emergency department (ED) and outpatient visits and provider acceptance of test recommendations. Costs were estimated using national data sources. RESULTS There were 205 tested patients PS matched to 820 untested patients. Hospitalization rate was 9.8% in the tested group vs. 16.1% in the untested group (RR = 0.61, 95% CI = 0.39-0.95, p = 0.027), ED visit rate was 4.4% in the tested group vs. 15.4% in the untested group (RR = 0.29, 95% CI = 0.15-0.55, p = 0.0002) and outpatient visit rate was 71.7% in the tested group vs. 36.5% in the untested group (RR = 1.97, 95% CI = 1.74-2.23, p < 0.0001). The rate of overall HRU was 72.2% in the tested group vs. 49.0% in the untested group (RR = 1.47, 95% CI = 1.32-1.64, p < 0.0001). Potential cost savings were estimated at $218 (mean) in the tested group. The provider majority (95%) considered the test helpful and 46% followed CDST provided recommendations. CONCLUSION Patients CYP DNA tested and treated according to the personalized prescribing system had a significant decrease in hospitalizations and emergency department visits, resulting in potential cost savings. Providers had a high satisfaction rate with the clinical utility of the system and followed recommendations when appropriate.
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Affiliation(s)
- D Brixner
- a a Department of Pharmacotherapy , College of Pharmacy, and Program in Personalized Health, University of Utah , Salt Lake City , UT , USA
| | - E Biltaji
- a a Department of Pharmacotherapy , College of Pharmacy, and Program in Personalized Health, University of Utah , Salt Lake City , UT , USA
| | - A Bress
- b b Department of Pharmacotherapy , College of Pharmacy, University of Utah , Salt Lake City , UT , USA
| | - S Unni
- b b Department of Pharmacotherapy , College of Pharmacy, University of Utah , Salt Lake City , UT , USA
| | - X Ye
- b b Department of Pharmacotherapy , College of Pharmacy, University of Utah , Salt Lake City , UT , USA
| | - T Mamiya
- c c Genelex Corporation , Seattle , WA , USA
| | - K Ashcraft
- c c Genelex Corporation , Seattle , WA , USA
| | - J Biskupiak
- a a Department of Pharmacotherapy , College of Pharmacy, and Program in Personalized Health, University of Utah , Salt Lake City , UT , USA
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Qiao W, Yang Y, Sebra R, Mendiratta G, Gaedigk A, Desnick RJ, Scott SA. Long-Read Single Molecule Real-Time Full Gene Sequencing of Cytochrome P450-2D6. Hum Mutat 2015; 37:315-23. [PMID: 26602992 DOI: 10.1002/humu.22936] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 11/13/2015] [Indexed: 12/30/2022]
Abstract
The cytochrome P450-2D6 (CYP2D6) enzyme metabolizes ∼25% of common medications, yet homologous pseudogenes and copy number variants (CNVs) make interrogating the polymorphic CYP2D6 gene with short-read sequencing challenging. Therefore, we developed a novel long-read, full gene CYP2D6 single molecule real-time (SMRT) sequencing method using the Pacific Biosciences platform. Long-range PCR and CYP2D6 SMRT sequencing of 10 previously genotyped controls identified expected star (*) alleles, but also enabled suballele resolution, diplotype refinement, and discovery of novel alleles. Coupled with an optimized variant-calling pipeline, CYP2D6 SMRT sequencing was highly reproducible as triplicate intra- and inter-run nonreference genotype results were completely concordant. Importantly, targeted SMRT sequencing of upstream and downstream CYP2D6 gene copies characterized the duplicated allele in 15 control samples with CYP2D6 CNVs. The utility of CYP2D6 SMRT sequencing was further underscored by identifying the diplotypes of 14 samples with discordant or unclear CYP2D6 configurations from previous targeted genotyping, which again included suballele resolution, duplicated allele characterization, and discovery of a novel allele and tandem arrangement. Taken together, long-read CYP2D6 SMRT sequencing is an innovative, reproducible, and validated method for full-gene characterization, duplication allele-specific analysis, and novel allele discovery, which will likely improve CYP2D6 metabolizer phenotype prediction for both research and clinical testing applications.
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Affiliation(s)
- Wanqiong Qiao
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, 10029
| | - Yao Yang
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, 10029
| | - Robert Sebra
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, 10029.,Icahn Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, New York, 10029
| | - Geetu Mendiratta
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, 10029
| | - Andrea Gaedigk
- Division of Clinical Pharmacology, Toxicology & Therapeutic Innovation, Children's Mercy Kansas City, Kansas City, Missouri, 64108.,School of Medicine, University of Missouri-Kansas City, Kansas City, Missouri, 64108
| | - Robert J Desnick
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, 10029
| | - Stuart A Scott
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, 10029
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Malhi GS, Bassett D, Boyce P, Bryant R, Fitzgerald PB, Fritz K, Hopwood M, Lyndon B, Mulder R, Murray G, Porter R, Singh AB. Royal Australian and New Zealand College of Psychiatrists clinical practice guidelines for mood disorders. Aust N Z J Psychiatry 2015; 49:1087-206. [PMID: 26643054 DOI: 10.1177/0004867415617657] [Citation(s) in RCA: 511] [Impact Index Per Article: 56.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVES To provide guidance for the management of mood disorders, based on scientific evidence supplemented by expert clinical consensus and formulate recommendations to maximise clinical salience and utility. METHODS Articles and information sourced from search engines including PubMed and EMBASE, MEDLINE, PsycINFO and Google Scholar were supplemented by literature known to the mood disorders committee (MDC) (e.g., books, book chapters and government reports) and from published depression and bipolar disorder guidelines. Information was reviewed and discussed by members of the MDC and findings were then formulated into consensus-based recommendations and clinical guidance. The guidelines were subjected to rigorous successive consultation and external review involving: expert and clinical advisors, the public, key stakeholders, professional bodies and specialist groups with interest in mood disorders. RESULTS The Royal Australian and New Zealand College of Psychiatrists clinical practice guidelines for mood disorders (Mood Disorders CPG) provide up-to-date guidance and advice regarding the management of mood disorders that is informed by evidence and clinical experience. The Mood Disorders CPG is intended for clinical use by psychiatrists, psychologists, physicians and others with an interest in mental health care. CONCLUSIONS The Mood Disorder CPG is the first Clinical Practice Guideline to address both depressive and bipolar disorders. It provides up-to-date recommendations and guidance within an evidence-based framework, supplemented by expert clinical consensus. MOOD DISORDERS COMMITTEE Professor Gin Malhi (Chair), Professor Darryl Bassett, Professor Philip Boyce, Professor Richard Bryant, Professor Paul Fitzgerald, Dr Kristina Fritz, Professor Malcolm Hopwood, Dr Bill Lyndon, Professor Roger Mulder, Professor Greg Murray, Professor Richard Porter and Associate Professor Ajeet Singh. INTERNATIONAL EXPERT ADVISORS Professor Carlo Altamura, Dr Francesco Colom, Professor Mark George, Professor Guy Goodwin, Professor Roger McIntyre, Dr Roger Ng, Professor John O'Brien, Professor Harold Sackeim, Professor Jan Scott, Dr Nobuhiro Sugiyama, Professor Eduard Vieta, Professor Lakshmi Yatham. AUSTRALIAN AND NEW ZEALAND EXPERT ADVISORS Professor Marie-Paule Austin, Professor Michael Berk, Dr Yulisha Byrow, Professor Helen Christensen, Dr Nick De Felice, A/Professor Seetal Dodd, A/Professor Megan Galbally, Dr Josh Geffen, Professor Philip Hazell, A/Professor David Horgan, A/Professor Felice Jacka, Professor Gordon Johnson, Professor Anthony Jorm, Dr Jon-Paul Khoo, Professor Jayashri Kulkarni, Dr Cameron Lacey, Dr Noeline Latt, Professor Florence Levy, A/Professor Andrew Lewis, Professor Colleen Loo, Dr Thomas Mayze, Dr Linton Meagher, Professor Philip Mitchell, Professor Daniel O'Connor, Dr Nick O'Connor, Dr Tim Outhred, Dr Mark Rowe, Dr Narelle Shadbolt, Dr Martien Snellen, Professor John Tiller, Dr Bill Watkins, Dr Raymond Wu.
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Affiliation(s)
- Gin S Malhi
- Discipline of Psychiatry, Kolling Institute, Sydney Medical School, University of Sydney, Sydney, NSW, Australia CADE Clinic, Department of Psychiatry, Royal North Shore Hospital, St Leonards, NSW, Australia
| | - Darryl Bassett
- School of Psychiatry and Clinical Neurosciences, University of Western Australia, Perth, WA, Australia School of Medicine, University of Notre Dame, Perth, WA, Australia
| | - Philip Boyce
- Discipline of Psychiatry, Sydney Medical School, Westmead Clinical School, University of Sydney, Sydney, NSW, Australia
| | - Richard Bryant
- School of Psychology, University of New South Wales, Sydney, NSW, Australia
| | - Paul B Fitzgerald
- Monash Alfred Psychiatry Research Centre (MAPrc), Monash University Central Clinical School and The Alfred, Melbourne, VIC, Australia
| | - Kristina Fritz
- CADE Clinic, Discipline of Psychiatry, Sydney Medical School - Northern, University of Sydney, Sydney, NSW, Australia
| | - Malcolm Hopwood
- Department of Psychiatry, University of Melbourne, Melbourne, VIC, Australia
| | - Bill Lyndon
- Sydney Medical School, University of Sydney, Sydney, NSW, Australia Mood Disorders Unit, Northside Clinic, Greenwich, NSW, Australia ECT Services Northside Group Hospitals, Greenwich, NSW, Australia
| | - Roger Mulder
- Department of Psychological Medicine, University of Otago-Christchurch, Christchurch, New Zealand
| | - Greg Murray
- Department of Psychological Sciences, School of Health Sciences, Swinburne University of Technology, Melbourne, VIC, Australia
| | - Richard Porter
- Department of Psychological Medicine, University of Otago-Christchurch, Christchurch, New Zealand
| | - Ajeet B Singh
- School of Medicine, Deakin University, Geelong, VIC, Australia
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Zhu Q, Liu H, Chute CG, Ferber M. EHR based Genetic Testing Knowledge Base (iGTKB) Development. BMC Med Inform Decis Mak 2015; 15 Suppl 4:S3. [PMID: 26606281 PMCID: PMC4660117 DOI: 10.1186/1472-6947-15-s4-s3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The gap between a large growing number of genetic tests and a suboptimal clinical workflow of incorporating these tests into regular clinical practice poses barriers to effective reliance on advanced genetic technologies to improve quality of healthcare. A promising solution to fill this gap is to develop an intelligent genetic test recommendation system that not only can provide a comprehensive view of genetic tests as education resources, but also can recommend the most appropriate genetic tests to patients based on clinical evidence. In this study, we developed an EHR based Genetic Testing Knowledge Base for Individualized Medicine (iGTKB). METHODS We extracted genetic testing information and patient medical records from EHR systems at Mayo Clinic. Clinical features have been semi-automatically annotated from the clinical notes by applying a Natural Language Processing (NLP) tool, MedTagger suite. To prioritize clinical features for each genetic test, we compared odds ratio across four population groups. Genetic tests, genetic disorders and clinical features with their odds ratios have been applied to establish iGTKB, which is to be integrated into the Genetic Testing Ontology (GTO). RESULTS Overall, there are five genetic tests operated with sample size greater than 100 in 2013 at Mayo Clinic. A total of 1,450 patients who was tested by one of the five genetic tests have been selected. We assembled 243 clinical features from the Human Phenotype Ontology (HPO) for these five genetic tests. There are 60 clinical features with at least one mention in clinical notes of patients taking the test. Twenty-eight clinical features with high odds ratio (greater than 1) have been selected as dominant features and deposited into iGTKB with their associated information about genetic tests and genetic disorders. CONCLUSIONS In this study, we developed an EHR based genetic testing knowledge base, iGTKB. iGTKB will be integrated into the GTO by providing relevant clinical evidence, and ultimately to support development of genetic testing recommendation system, iGenetics.
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Winner JG, Dechairo B. Combinatorial Versus Individual Gene Pharmacogenomic Testing in Mental Health: A Perspective on Context and Implications on Clinical Utility. THE YALE JOURNAL OF BIOLOGY AND MEDICINE 2015; 88:375-82. [PMID: 26604861 PMCID: PMC4654186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Pharmacogenomic testing in mental health has not yet reached its full potential. An important reason for this involves differentiating individual gene testing (IGT) from a combinatorial pharmacogenomic (CPGx) approach. With IGT, any given gene reveals specific information that may, in turn, pertain to a smaller number of medications. CPGx approaches attempt to encompass more complete genomic information by combining moderate risk alleles and synergistically viewing the results from the perspective of the medication. This manuscript will discuss IGT and CPGx approaches to psychiatric pharmacogenomics and review the clinical validity, clinical utility, and economic parameters of both.
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Affiliation(s)
- Joel G. Winner
- To whom all correspondence should be addressed: Joel G. Winner, MD, 2595 Canyon Boulevard, Suite 100, Boulder, CO 80302; Tele: 720-920-9174; Fax: 720-920-9307;
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Summaries of plenary, symposia, and oral sessions at the XXII World Congress of Psychiatric Genetics, Copenhagen, Denmark, 12-16 October 2014. Psychiatr Genet 2015; 26:1-47. [PMID: 26565519 DOI: 10.1097/ypg.0000000000000112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The XXII World Congress of Psychiatric Genetics, sponsored by the International Society of Psychiatric Genetics, took place in Copenhagen, Denmark, on 12-16 October 2014. A total of 883 participants gathered to discuss the latest findings in the field. The following report was written by student and postdoctoral attendees. Each was assigned one or more sessions as a rapporteur. This manuscript represents topics covered in most, but not all of the oral presentations during the conference, and contains some of the major notable new findings reported.
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Haga SB, Moaddeb J, Mills R, Patel M, Kraus W, Allen LaPointe NM. Incorporation of pharmacogenetic testing into medication therapy management. Pharmacogenomics 2015; 16:1931-41. [PMID: 26555559 DOI: 10.2217/pgs.15.124] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
AIM To assess feasibility and patient satisfaction with a pharmacist-delivered medication therapy management (MTM) plus pharmacogenetic (PGx) testing service. METHODS Thirty patients from a cardiology outpatient clinic were enrolled to attend two MTM sessions, undergo PGx testing and complete pre- and post-intervention surveys. Outcome measures included duration of MTM sessions, clinical application of test results, self-reported medication adherence, patient recall of results and perceived value of testing and MTM. RESULTS Overall, patients were very satisfied with the MTM plus PGx testing service. About half of participants (47%) were able to accurately recall their PGx test results. Comparable to MTM without PGx testing, the first MTM session averaged 40 min and the follow-up MTM session averaged 15 min. CONCLUSION PGx testing incorporated into a clinical MTM service offered by pharmacists may be a feasible delivery model and is satisfactory to patients.
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Affiliation(s)
- Susanne B Haga
- Center for Applied Genomics & Precision Medicine, Duke University School of Medicine, 201 Trent Dr, Durham, NC 27710, USA
| | - Jivan Moaddeb
- Center for Applied Genomics & Precision Medicine, Duke University School of Medicine, 201 Trent Dr, Durham, NC 27710, USA
| | - Rachel Mills
- Center for Applied Genomics & Precision Medicine, Duke University School of Medicine, 201 Trent Dr, Durham, NC 27710, USA
| | - Mahesh Patel
- Center for Applied Genomics & Precision Medicine, Duke University School of Medicine, 201 Trent Dr, Durham, NC 27710, USA
| | - William Kraus
- Center for Applied Genomics & Precision Medicine, Duke University School of Medicine, 201 Trent Dr, Durham, NC 27710, USA
| | - Nancy M Allen LaPointe
- Center for Applied Genomics & Precision Medicine, Duke University School of Medicine, 201 Trent Dr, Durham, NC 27710, USA
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Pouget JG, Shams TA, Tiwari AK, Müller DJ. Pharmacogenetics and outcome with antipsychotic drugs. DIALOGUES IN CLINICAL NEUROSCIENCE 2015. [PMID: 25733959 PMCID: PMC4336924 DOI: 10.31887/dcns.2014.16.4/jpouget] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Antipsychotic medications are the gold-standard treatment for schizophrenia, and are often prescribed for other mental conditions. However, the efficacy and side-effect profiles of these drugs are heterogeneous, with large interindividual variability. As a result, treatment selection remains a largely trial-and-error process, with many failed treatment regimens endured before finding a tolerable balance between symptom management and side effects. Much of the interindividual variability in response and side effects is due to genetic factors (heritability, h2~ 0.60-0.80). Pharmacogenetics is an emerging field that holds the potential to facilitate the selection of the best medication for a particular patient, based on his or her genetic information. In this review we discuss the most promising genetic markers of antipsychotic treatment outcomes, and present current translational research efforts that aim to bring these pharmacogenetic findings to the clinic in the near future.
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Affiliation(s)
- Jennie G Pouget
- Pharmacogenetics Research Clinic, Campbell Family Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada ; Institute of Medical Sciences, University of Toronto, Toronto, Ontario, Canada
| | - Tahireh A Shams
- Pharmacogenetics Research Clinic, Campbell Family Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Department of Science, Ryerson University,Toronto, Ontario, Canada
| | - Arun K Tiwari
- Pharmacogenetics Research Clinic, Campbell Family Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Daniel J Müller
- Pharmacogenetics Research Clinic, Campbell Family Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Department of Psychiatry University of Toronto, Toronto, Ontario, Canada
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229
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Gershon ES, Alliey-Rodriguez N, Grennan K. Ethical and public policy challenges for pharmacogenomics. DIALOGUES IN CLINICAL NEUROSCIENCE 2015. [PMID: 25733960 PMCID: PMC4336925 DOI: 10.31887/dcns.2014.16.4/egershon] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
It is timely to consider the ethical and social questions raised by progress in pharmacogenomics, based on the current importance of pharmacogenomics for avoidance of predictable side effects of drugs, and for correct choice of medications in certain cancers. It has been proposed that the entire population be genotyped for drug-metabolizing enzyme polymorphisms, as a measure that would prevent many untoward and dangerous drug reactions. Pharmacologic treatment targeting based on genomics of disease can be expected to increase greatly in the coming years. Policy and ethical issues exist on consent for large-scale genomic pharmacogenomic data collection, public vs corporate ownership of genomic research results, testing efficacy and safety of drugs used for rare genomic indications, and accessibility of treatments based on costly research that is applicable to relatively few patients. In major psychiatric disorders and intellectual deficiency, rare and de novo deletion or duplication of chromosomal segments (copy number variation), in the aggregate, are common causes of increased risk. This implies that the policy problems of pharmacogenomics will be particularly important for the psychiatric disorders.
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Affiliation(s)
- Elliot S Gershon
- Department of Psychiatry and Behavioral Neuroscience; Department of Human Genetics; University of Chicago, Illinois, USA
| | - Ney Alliey-Rodriguez
- Department of Psychiatry and Behavioral Neuroscience; University of Chicago, Illinois, USA
| | - Kay Grennan
- Department of Psychiatry and Behavioral Neuroscience; University of Chicago, Illinois, USA
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230
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Kisor DF, Bright DR, Chen J, Smith TR. Academic and professional pharmacy education: a pharmacogenomics certificate training program. Per Med 2015; 12:563-573. [DOI: 10.2217/pme.15.31] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Aim: The aim of this study was to evaluate a pharmacogenomics certificate training program relative to pharmacist competencies in basic genetic concepts, genetics and disease, pharmacogenetics/pharmacogenomics and ethical, legal and social implication. Methods: Participants, including pharmacists, pharmacy students and pharmacy educators completed a survey related to to the competency statements. Following the pre-program survey, participants completed a 6-week home self-study with subject matter including basic science (three chapters) and clinical application of pharmacogenomics (eight chapters). The participants completed a quiz for each of the self-study chapters. Following the self-study, participants completed a day-long, 7-h live program which included a review of the competency statements and counseling sessions with seven different simulated patients (primarily pharmacy students). Participants then completed a post-program survey which included the same items as the pre-program survey. Results: Specifically, for the pharmacist participants, the average score of the self-study quizzes was 91%. For the pharmacists specifically, there was a statistically significant increase in self-assessed perception of competence related to pharmacogenomics. Additionally, it was observed that recommendations related to specific drug–gene interactions for the simulated patients were addressed correctly 95% of the time across all participant–patient encounters. Conclusion: Self-study and a live, interactive component in the certificate training program led to increased self-understanding of defined pharmacogenomics competencies. Additionally, pharmacy students, in the role of simulated patients gained knowledge during the live component of the program. This type of program, especially if made available through electronic-based platforms can serve to educate pharmacists and increase the uptake of pharmacogenomics in various healthcare settings.
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Affiliation(s)
- David F Kisor
- Department of Pharmaceutical Sciences, Manchester University, College of Pharmacy Natural & Health Sciences, Pharmacy Program, Fort Wayne, IN, USA
| | - David R Bright
- Department of Pharmaceutical Sciences, Ferris State University, College of Pharmacy, Big Rapids, MI, USA
| | - Jack Chen
- Department of Pharmaceutical Sciences, Manchester University, College of Pharmacy Natural & Health Sciences, Pharmacy Program, Fort Wayne, IN, USA
| | - Thomas R Smith
- Department of Pharmacy Practice, Manchester University, College of Pharmacy Natural & Health Sciences, Pharmacy Program, Fort Wayne, IN, USA
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231
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Walden LM, Brandl EJ, Changasi A, Sturgess JE, Soibel A, Notario JFD, Cheema S, Braganza N, Marshe VS, Freeman N, Tiwari AK, Kennedy JL, Müller DJ. Physicians' opinions following pharmacogenetic testing for psychotropic medication. Psychiatry Res 2015; 229:913-8. [PMID: 26298505 DOI: 10.1016/j.psychres.2015.07.032] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Revised: 06/18/2015] [Accepted: 07/12/2015] [Indexed: 11/25/2022]
Abstract
Pharmacogenetics seeks to improve patient drug response and decrease side effects by personalizing prescriptions using genetic information. Since 2012, by one estimate, the number of patients who have had pharmacogenetic testing has doubled and this number is expected to double again by 2015. Given the increasing evidence for genetic influences on treatment response, we deemed it important to study physicians' opinions of pharmacogenetic testing. Surveys were completed by 168 Canadian physicians who had ordered at least one pharmacogenetic test (in particular for CYP2D6 or CYP2C19) for the prescription of psychiatric medication. Our results indicated that 80% of respondents believe genetic testing would become common standard in psychiatric drug treatment and 76% of respondents reported satisfactory or higher than satisfactory understanding of the pharmacogenetic report provided. Significantly more male physicians believed they had a higher understanding of the pharmacogenetic report compared to female physicians. To our knowledge, this is the only study that has assessed physicians' opinions of pharmacogenetic testing for psychotropic medication after they had received a pharmacogenetic report. Our results demonstrate a positive opinion of physicians on pharmacogenetics and indicate great potential for future clinical application.
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Affiliation(s)
- Lucas M Walden
- Pharmacogenetic Research Clinic, Campbell Family Mental Health Research Institute, Center for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Eva J Brandl
- Pharmacogenetic Research Clinic, Campbell Family Mental Health Research Institute, Center for Addiction and Mental Health, Toronto, Ontario, Canada; Department of Psychiatry and Psychotherapy, Campus Mitte, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Amtul Changasi
- Pharmacogenetic Research Clinic, Campbell Family Mental Health Research Institute, Center for Addiction and Mental Health, Toronto, Ontario, Canada; University of Toronto, Scarborough, Ontario, Canada
| | - Jessica E Sturgess
- Pharmacogenetic Research Clinic, Campbell Family Mental Health Research Institute, Center for Addiction and Mental Health, Toronto, Ontario, Canada; Department of Internal Medicine, Rush University Medical Center, Chicago, IL, USA
| | - Alexander Soibel
- Pharmacogenetic Research Clinic, Campbell Family Mental Health Research Institute, Center for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Janna Fe D Notario
- Pharmacogenetic Research Clinic, Campbell Family Mental Health Research Institute, Center for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Sheraz Cheema
- Pharmacogenetic Research Clinic, Campbell Family Mental Health Research Institute, Center for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Nicole Braganza
- Pharmacogenetic Research Clinic, Campbell Family Mental Health Research Institute, Center for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Victoria S Marshe
- Pharmacogenetic Research Clinic, Campbell Family Mental Health Research Institute, Center for Addiction and Mental Health, Toronto, Ontario, Canada; Institute of Medical Science, Faculty of Medicine, University of Toronto, Toronto, Canada
| | - Natalie Freeman
- Pharmacogenetic Research Clinic, Campbell Family Mental Health Research Institute, Center for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Arun K Tiwari
- Pharmacogenetic Research Clinic, Campbell Family Mental Health Research Institute, Center for Addiction and Mental Health, Toronto, Ontario, Canada
| | - James L Kennedy
- Pharmacogenetic Research Clinic, Campbell Family Mental Health Research Institute, Center for Addiction and Mental Health, Toronto, Ontario, Canada; Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada.
| | - Daniel J Müller
- Pharmacogenetic Research Clinic, Campbell Family Mental Health Research Institute, Center for Addiction and Mental Health, Toronto, Ontario, Canada; Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada.
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232
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Chang KL, Weitzel K, Schmidt S. Pharmacogenetics: Using Genetic Information to Guide Drug Therapy. Am Fam Physician 2015; 92:588-594. [PMID: 26447442 PMCID: PMC4729205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Clinical pharmacogenetics, the use of genetic data to guide drug therapy decisions, is beginning to be used for medications commonly prescribed by family physicians. However, clinicians are largely unfamiliar with principles supporting clinical use of this type of data. For example, genetic variability in the cytochrome P450 2D6 drug metabolizing enzyme can alter the clinical effects of some opioid analgesics (e.g., codeine, tramadol), whereas variability in the CYP2C19 enzyme affects the antiplatelet agent clopidogrel. If testing is performed, patients who are ultrarapid or poor metabolizers of CYP2D6 should avoid codeine use (and possibly tramadol, hydrocodone, and oxycodone) because of the potential for increased toxicity or lack of effectiveness. Patients undergoing percutaneous coronary intervention for acute coronary syndromes who are known to be poor metabolizers of CYP2C19 should consider alternate antiplatelet therapy (e.g., ticagrelor, prasugrel). Some guidelines are available that address appropriate drug therapy changes, and others are in development. Additionally, a number of clinical resources are emerging to support family physicians in the use of pharmacogenetics. When used appropriately, pharmacogenetic testing can be a practical tool to optimize drug therapy and avoid medication adverse effects.
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Affiliation(s)
- Ku-Lang Chang
- University of Florida College of Medicine, Gainesville, FL, USA
| | - Kristin Weitzel
- University of Florida College of Pharmacy, Gainesville, FL, USA
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234
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Gaedigk A, Riffel AK, Leeder JS. CYP2D6 Haplotype Determination Using Long Range Allele-Specific Amplification: Resolution of a Complex Genotype and a Discordant Genotype Involving the CYP2D6*59 Allele. J Mol Diagn 2015; 17:740-8. [PMID: 26335396 DOI: 10.1016/j.jmoldx.2015.06.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Revised: 05/14/2015] [Accepted: 06/22/2015] [Indexed: 01/08/2023] Open
Abstract
Cytochrome P450 (CYP) 2D6, a major contributor to the metabolism and bioactivation of many clinically used drugs, is encoded by a complex, highly polymorphic gene locus. To aid in the characterization of CYP2D6 allelic variation, we developed allele-specific long-range PCR (ASXL-PCR) to amplify only the allele of interest for further characterization by PCR. This development was achieved utilizing single-nucleotide polymorphisms in the upstream region of CYP2D6 and a universal CYP2D6-specific reverse primer. This approach was assessed and optimized on samples with known genotypes. The application of ASXL-PCR clarified a case with a complex genotype (CYP2D6*2x2/*4N+*4) by amplifying the duplicated gene units separately for subsequent analysis. Furthermore, ASXL-PCR and subsequent sequence analysis also resolved genotype discord in a mother/daughter relationship by revealing the presence of the CYP2D6*59 allelic variant in both individuals. Finally, we demonstrated that the 2939G>A single-nucleotide polymorphism present on CYP2D6*59 interfered with the TaqMan genotype assay that detected 2850C>T, causing false genotype assignments. Assay interference was resolved using an alternative TaqMan genotype assay currently available as a custom-made assay. These examples demonstrate the utility of ASXL-PCR for improved CYP2D6 allele/haplotype characterization. This fast, easy-to-perform method is not limited to CYP2D6 but can be adapted to any gene locus for which polymorphic sites are known.
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Affiliation(s)
- Andrea Gaedigk
- Division of Clinical Pharmacology, Toxicology and Therapeutic Innovation, Children's Mercy Kansas City, Kansas City, Missouri; Department of Pediatrics, University of Missouri-Kansas City, Kansas City, Missouri.
| | - Amanda K Riffel
- Division of Clinical Pharmacology, Toxicology and Therapeutic Innovation, Children's Mercy Kansas City, Kansas City, Missouri
| | - J Steven Leeder
- Division of Clinical Pharmacology, Toxicology and Therapeutic Innovation, Children's Mercy Kansas City, Kansas City, Missouri; Department of Pediatrics, University of Missouri-Kansas City, Kansas City, Missouri
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235
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Interindividual variability of CYP2C19-catalyzed drug metabolism due to differences in gene diplotypes and cytochrome P450 oxidoreductase content. THE PHARMACOGENOMICS JOURNAL 2015; 16:375-87. [PMID: 26323597 PMCID: PMC4775436 DOI: 10.1038/tpj.2015.58] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Revised: 05/19/2015] [Accepted: 06/23/2015] [Indexed: 02/01/2023]
Abstract
Large interindividual variability has been observed in the metabolism of CYP2C19 substrates in vivo. The study aimed to evaluate sources of this variability in CYP2C19 activity, focusing on CYP2C19 diplotypes and the cytochrome P450 oxidoreductase (POR). CYP2C19 gene analysis was carried out on 347 human liver samples. CYP2C19 activity assayed using human liver microsomes confirmed a significant a priori predicted rank order for (S)-mephenytoin hydroxylase activity of CYP2C19*17/*17 > *1B/*17 > *1B/*1B > *2A/*17 > *1B/*2A > *2A/*2A diplotypes. In a multivariate analysis, the CYP2C19*2A allele and POR protein content were associated with CYP2C19 activity. Further analysis indicated a strong effect of the CYP2C19*2A, but not the *17, allele on both metabolic steps in the conversion of clopidogrel to its active metabolite. The present study demonstrates that interindividual variability in CYP2C19 activity is due to differences in both CYP2C19 protein content associated with gene diplotypes and the POR concentration.
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236
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Bauer IE, Graham DP, Soares JC, Nielsen DA. Serotonergic gene variation in substance use pharmacotherapy: a systematic review. Pharmacogenomics 2015; 16:1307-14. [PMID: 26265436 DOI: 10.2217/pgs.15.72] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Drug addiction is a serious disease with damaging effects on the brain and physical health. Despite the increase in the number of affected individuals, there are few effective pharmacological treatment options for substance use disorders. The study of the influence of an individual's genetic features on the treatment response may help to identify more efficacious treatment options. This systematic review focuses on the serotonergic system because of its relevant role in mood and impulse control disorders, and its contribution to the development and maintenance of drug use disorders. In particular, we examine the role of serotonergic genes in the response to pharmacotherapy for alcohol, cocaine and nicotine addiction. Current evidence suggests that genetic variability of the serotonergic biosynthesis enzyme tryptophan hydroxylase 2 (TPH2) and the serotonin transporter (SLC6A4) genes mediates the efficacy of several addiction treatments, such as ondansetron and disulfiram, and the antidepressants bupropion, nortriptyline and sertraline.
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Affiliation(s)
- Isabelle E Bauer
- Department of Psychiatry & Behavioral Sciences, The University of Texas Health Science Center at Houston, Houston, TX, USA
| | - David P Graham
- Michael E DeBakey VA Medical Center, Baylor College of Medicine, 2002 Holcombe Boulevard, Research 151, Building 110, Suite 227, Houston, TX 77030, USA
| | - Jair C Soares
- Department of Psychiatry & Behavioral Sciences, The University of Texas Health Science Center at Houston, Houston, TX, USA
| | - David A Nielsen
- Michael E DeBakey VA Medical Center, Baylor College of Medicine, 2002 Holcombe Boulevard, Research 151, Building 110, Suite 227, Houston, TX 77030, USA
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237
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Singh AB. Improved Antidepressant Remission in Major Depression via a Pharmacokinetic Pathway Polygene Pharmacogenetic Report. CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE 2015; 13:150-6. [PMID: 26243841 PMCID: PMC4540033 DOI: 10.9758/cpn.2015.13.2.150] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Revised: 01/04/2015] [Accepted: 01/07/2015] [Indexed: 12/26/2022]
Abstract
Objective Major depressive disorder (MDD) is projected to be a leading cause of disability globally by 2030. Only a minority of patients remit with antidepressants. If assay of polymorphisms influencing central nervous system (CNS) bioavailability could guide prescribers to more effectively dose patients, remission rates may improve and the burden of disease from MDD reduce. Hepatic and blood brain barrier (BBB) polymorphisms appear to influence antidepressant CNS bioavailability. Methods A 12-week prospective double blind randomized genetically guided versus unguided trial of antidepressant dosing in Caucasian adults with MDD (n=148) was conducted. Results Subjects receiving genetically guided prescribing had a 2.52-fold greater chance of remission (95% confidence interval [CI]=1.71–3.73, z=4.66, p<0.0001). The number needed to genotype (NNG)=3 (95% CI=1.7–3.5) to produce an additional remission. Conclusion These data suggest that a pharmacogenetic dosing report (CNSDose®) improves antidepressant efficacy. The effect size was sufficient that translation to clinical care may arise if results are independently replicated.
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238
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Hertz DL, Snavely AC, McLeod HL, Walko CM, Ibrahim JG, Anderson S, Weck KE, Magrinat G, Olajide O, Moore S, Raab R, Carrizosa DR, Corso S, Schwartz G, Peppercorn JM, Evans JP, Jones DR, Desta Z, Flockhart DA, Carey LA, Irvin WJ. In vivo assessment of the metabolic activity of CYP2D6 diplotypes and alleles. Br J Clin Pharmacol 2015; 80:1122-30. [PMID: 25907378 DOI: 10.1111/bcp.12665] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 04/07/2015] [Accepted: 04/11/2015] [Indexed: 01/13/2023] Open
Abstract
AIMS A prospectively enrolled patient cohort was used to assess whether the prediction of CYP2D6 phenotype activity from genotype data could be improved by reclassification of diplotypes or alleles. METHODS Three hundred and fifty-five patients receiving tamoxifen 20 mg were genotyped for CYP2D6 and tamoxifen metabolite concentrations were measured. The endoxifen : N-desmethly-tamoxifen metabolic ratio, as a surrogate of CYP2D6 activity, was compared across four diplotypes (EM/IM, EM/PM, IM/IM, IM/PM) that are typically collapsed into an intermediate metabolizer (IM) phenotype. The relative metabolic activity of each allele type (UM, EM, IM, and PM) and each EM and IM allele was estimated for comparison with the activity scores typically assigned, 2, 1, 0.5 and 0, respectively. RESULTS Each of the four IM diplotypes have distinct CYP2D6 activity from each other and from the EM and PM phenotype groups (each P < 0.05). Setting the activity of an EM allele at 1.0, the relative activities of a UM, IM and PM allele were 0.85, 0.67 and 0.52, respectively. The activity of the EM alleles were statistically different (P < 0.0001), with the CYP2D6*2 allele (scaled activity = 0.63) closer in activity to an IM than an EM allele. The activity of the IM alleles were also statistically different (P = 0.014). CONCLUSION The current systems for translating CYP2D6 genotype into phenotype are not optimally calibrated, particularly in regards to IM diplotypes and the *2 allele. Additional research is needed to improve the prediction of CYP2D6 activity from genetic data for individualized dosing of CYP2D6 dependent drugs.
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Affiliation(s)
| | - Anna C Snavely
- RTI International, Research Triangle Park, NC, 27709-2194, USA
| | | | | | - Joseph G Ibrahim
- University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Steven Anderson
- Laboratory Corporation of America, Burlington, NC, 27215, USA
| | - Karen E Weck
- University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Gustav Magrinat
- Moses Cone Health Cancer Center, Greensboro, NC, 27401-1020, USA
| | | | - Susan Moore
- Rex Hematology Oncology Associates, Raleigh, NC, 27607, USA
| | - Rachel Raab
- Brody School of Medicine at East Carolina University, Greenville, NC, 27834, USA
| | | | - Steven Corso
- Palmetto Hematology Oncology, Spartanburg, SC, 29303, USA
| | - Garry Schwartz
- Levine Cancer Institute Concord, Concord, NC, 28025, USA
| | | | - James P Evans
- University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | | | | | | | - Lisa A Carey
- University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - William J Irvin
- University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA.,Bon Secours Cancer Institute, Richmond, VA, 23230, USA
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Varela N, Quiñones LA, Stojanova J, Garay J, Cáceres D, Cespedes S, Sasso J, Miranda C. Characterization of the CYP2D6 drug metabolizing phenotypes of the Chilean mestizo population through polymorphism analyses. Pharmacol Res 2015. [PMID: 26211952 DOI: 10.1016/j.phrs.2015.07.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
We tested the influence of four polymorphisms and gene duplication in CYP2D6 on in vivo enzyme activity in a Chilean mestizo population in order to identify the most relevant genetic profiles that account for observed phenotypes in this ethnic group. CYP2D6*2 (2850C>T), *3 (2549A>del), *4 (1846G>A), *17 (1023C>T) and gene duplication were determined by PCR-RFLP or PCRL in a group of 321 healthy volunteers. Individuals with different variant alleles were phenotyped by determining debrisoquine 4-hydroxylase activity as a metabolic ratio (MR) using a validated HPLC assay. Minor allele frequencies were 0.41, 0.01, 0.12 and 0.00 for CYP2D6*2, *3, *4 and *17 variants, respectively, and the duplication frequency was 0.003. Genotype analysis correlated with phenotypes in 18 of 23 subjects (78.3%). 11 subjects were extensive metabolizers (EM), 8 were intermediate metabolizers (IM), 2 were poor metabolizers (PM) and 2 were ultra-rapid metabolizers (UM) which is fairly coincident with expected phenotypes metabolic ratios ranged from 0.11 to 126.41. The influence of CYP2D6*3 was particularly notable, although only heterozygote carriers were present in our population. Individuals homozygous for *4 were always PM. As expected, the only subject with gene duplication was UM. In conclusion, there was a clear effect of genotype on observed CYP2D6 activity. Classification of EM, PM and UM through genotyping was useful to characterize CYP2D6 phenotype in the Chilean mestizo population.
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Affiliation(s)
- Nelson Varela
- Laboratory of Chemical Carcinogenesis and Pharmacogenetics, ICBM, Program of Molecular and Clinical Pharmacology, Faculty of Medicine, University of Chile, Chile; Department of Medical Technology, Faculty of Medicine, University of Chile, Chile
| | - Luis A Quiñones
- Laboratory of Chemical Carcinogenesis and Pharmacogenetics, ICBM, Program of Molecular and Clinical Pharmacology, Faculty of Medicine, University of Chile, Chile.
| | - Jana Stojanova
- Laboratory of Chemical Carcinogenesis and Pharmacogenetics, ICBM, Program of Molecular and Clinical Pharmacology, Faculty of Medicine, University of Chile, Chile
| | - Joselyn Garay
- Laboratory of Chemical Carcinogenesis and Pharmacogenetics, ICBM, Program of Molecular and Clinical Pharmacology, Faculty of Medicine, University of Chile, Chile
| | - Dante Cáceres
- Laboratory of Chemical Carcinogenesis and Pharmacogenetics, ICBM, Program of Molecular and Clinical Pharmacology, Faculty of Medicine, University of Chile, Chile; Environmental Health Program, School of Public Health, Faculty of Medicine, University of Chile, Chile
| | - Silvia Cespedes
- Laboratory of Chemical Carcinogenesis and Pharmacogenetics, ICBM, Program of Molecular and Clinical Pharmacology, Faculty of Medicine, University of Chile, Chile
| | - Jaime Sasso
- Laboratory of Chemical Carcinogenesis and Pharmacogenetics, ICBM, Program of Molecular and Clinical Pharmacology, Faculty of Medicine, University of Chile, Chile
| | - Carla Miranda
- Laboratory of Chemical Carcinogenesis and Pharmacogenetics, ICBM, Program of Molecular and Clinical Pharmacology, Faculty of Medicine, University of Chile, Chile
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Goulding R, Dawes D, Price M, Wilkie S, Dawes M. Genotype-guided drug prescribing: a systematic review and meta-analysis of randomized control trials. Br J Clin Pharmacol 2015; 80:868-77. [PMID: 25060532 PMCID: PMC4594730 DOI: 10.1111/bcp.12475] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Accepted: 07/21/2014] [Indexed: 01/11/2023] Open
Abstract
AIM Adverse drug events lead to increased morbidity, mortality and health care costs. Pharmacogenetic testing that guides drug prescribing has the potential to reduced adverse drug events and increase drug effectiveness. Our aim was to quantify the clinical effectiveness of genotype-guided prescribing. METHODS Three electronic databases were searched from January 1980 through December 2013. Studies were eligible if they were RCTs comparing genotype-guided prescribing with non-genetic informed prescribing, reported drug specific adverse drug events and clinical effectiveness outcomes. Two reviewers independently screened titles and abstracts, extracted data and assessed study quality. Meta-analyses of specific outcomes were conducted where data allowed. RESULTS Fifteen studies, involving 5688 patients and 19 drugs, met the inclusion and exclusion criteria. Eight studies had statistically significant results for their primary outcome in favour of genotype-guided prescribing. Nine studies evaluated genotype-guided warfarin dosing. Analysis of percentage of time in therapeutic international normalized ratio range (1952 individuals) showed a statistically significant benefit in favour of genotype-guided warfarin dosing (mean difference = 6.67; 95% CI 1.34, 12.0, I(2) = 80%). There was a statistically significant reduction in numbers of warfarin-related minor bleeding, major bleeding and thromboembolisms associated with genotype guided warfarin dosing, relative risk 0.57 (95% CI 0.33, 0.99; I(2) = 60%). It was not possible to meta-analyze genotype-guided dosing for other drugs. Of the six non-warfarin genotype-guided trials, two demonstrated a statistically significant benefit for their primary outcome, odds ratio 0.03 (95% CI 0.00, 0.62, P < 0.001) for abacavir. CONCLUSIONS There is evidence of improved clinical effectiveness associated with genotype-guided warfarin dosing.
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Affiliation(s)
- Rebecca Goulding
- Department of Family Practice, Faculty of Medicine, University of British Columbia, 3rd Floor David Strangway Building, 5950 University Boulevard, Vancouver, British Columbia, V6T 1Z3, Canada
| | - Diana Dawes
- Department of Family Practice, Faculty of Medicine, University of British Columbia, 3rd Floor David Strangway Building, 5950 University Boulevard, Vancouver, British Columbia, V6T 1Z3, Canada
| | - Morgan Price
- Department of Family Practice and Island Medical Program, University of Victoria, PO Box 1700 STN CSC, Victoria, British Columbia, V8W 2Y2, Canada
| | - Sabrina Wilkie
- Department of Family Practice, Faculty of Medicine, University of British Columbia, 3rd Floor David Strangway Building, 5950 University Boulevard, Vancouver, British Columbia, V6T 1Z3, Canada
| | - Martin Dawes
- Department of Family Practice, Faculty of Medicine, University of British Columbia, 3rd Floor David Strangway Building, 5950 University Boulevard, Vancouver, British Columbia, V6T 1Z3, Canada
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241
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Yang Y, Peter I, Scott SA. Pharmacogenetics in Jewish populations. ACTA ACUST UNITED AC 2015; 29:221-33. [PMID: 24867283 DOI: 10.1515/dmdi-2013-0069] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 04/04/2014] [Indexed: 12/24/2022]
Abstract
Spanning over 2000 years, the Jewish population has a long history of migration, population bottlenecks, expansions, and geographical isolation, which has resulted in a unique genetic architecture among the Jewish people. As such, many Mendelian disease genes and founder mutations for autosomal recessive diseases have been discovered in several Jewish groups, which have prompted recent genomic studies in the Jewish population on common disease susceptibility and other complex traits. Although few studies on the genetic determinants of drug response variability have been reported in the Jewish population, a number of unique pharmacogenetic variants have been discovered that are more common in Jewish populations than in other major racial groups. Notable examples identified in the Ashkenazi Jewish (AJ) population include the vitamin K epoxide reductase complex subunit 1 (VKORC1) c.106G>T (p.D36Y) variant associated with high warfarin dosing requirements and the recently reported cytochrome P450 2C19 (CYP2C19) allele, CYP2C19*4B, that harbors both loss-of-function [*4 (c.1A>G)] and increased-function [*17 (c.-806C>T)] variants on the same haplotype. These data are encouraging in that like other ethnicities and subpopulations, the Jewish population likely harbors numerous pharmacogenetic variants that are uncommon or absent in other larger racial groups and ethnicities. In addition to unique variants, common multi-ethnic variants in key drug metabolism genes (e.g., ABCB1, CYP2C8, CYP2C9, CYP2C19, CYP2D6, NAT2) have also been detected in the AJ and other Jewish groups. This review aims to summarize the currently available pharmacogenetics literature and discuss future directions for related research with this unique population.
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242
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Efectos de los inductores antiepilépticos en la neuropsicofarmacología: una cuestión ignorada. Parte II: cuestiones farmacológicas y comprensión adicional. REVISTA DE PSIQUIATRIA Y SALUD MENTAL 2015; 8:167-88. [DOI: 10.1016/j.rpsm.2014.10.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Accepted: 10/23/2014] [Indexed: 12/19/2022]
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Shabaruddin FH, Fleeman ND, Payne K. Economic evaluations of personalized medicine: existing challenges and current developments. Pharmgenomics Pers Med 2015; 8:115-26. [PMID: 26309416 PMCID: PMC4538689 DOI: 10.2147/pgpm.s35063] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Personalized medicine, with the aim of safely, effectively, and cost-effectively targeting treatment to a prespecified patient population, has always been a long-time goal within health care. It is often argued that personalizing treatment will inevitably improve clinical outcomes for patients and help achieve more effective use of health care resources. Demand is increasing for demonstrable evidence of clinical and cost-effectiveness to support the use of personalized medicine in health care. This paper begins with an overview of the existing challenges in conducting economic evaluations of genetics- and genomics-targeted technologies, as an example of personalized medicine. Our paper illustrates the complexity of the challenges faced by these technologies by highlighting the variations in the issues faced by diagnostic tests for somatic variations, generally referring to genetic variation in a tumor, and germline variations, generally referring to inherited genetic variation in enzymes involved in drug metabolic pathways. These tests are typically aimed at stratifying patient populations into subgroups on the basis of clinical effectiveness (response) or safety (avoidance of adverse events). The paper summarizes the data requirements for economic evaluations of genetics and genomics-based technologies while outlining that the main challenges relating to data requirements revolve around the availability and quality of existing data. We conclude by discussing current developments aimed to address the challenges of assessing the cost-effectiveness of genetics and genomics-based technologies, which revolve around two central issues that are interlinked: the need to adapt available evaluation methods and identifying who is responsible for generating evidence for these technologies.
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Affiliation(s)
| | - Nigel D Fleeman
- Liverpool Reviews and Implementation Group (LRiG), University of Liverpool, Liverpool, UK
| | - Katherine Payne
- Institute of Population Health, The University of Manchester, Manchester, UK
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244
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Fijal BA, Guo Y, Li SG, Ahl J, Goto T, Tanaka Y, Nisenbaum LK, Upadhyaya HP. CYP2D6 predicted metabolizer status and safety in adult patients with attention-deficit hyperactivity disorder participating in a large placebo-controlled atomoxetine maintenance of response clinical trial. J Clin Pharmacol 2015; 55:1167-74. [PMID: 25919121 DOI: 10.1002/jcph.530] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Accepted: 04/22/2015] [Indexed: 01/31/2023]
Abstract
Atomoxetine, which is indicated for treatment of attention-deficit hyperactivity disorder (ADHD), is predominantly metabolized by genetically polymorphic cytochrome P450 2D6 (CYP2D6). Based on identified CYP2D6 genotypes, individuals can be categorized into 4 phenotypic metabolizer groups as ultrarapid, extensive, intermediate, and poor. Previous studies have focused on observed differences between poor and extensive metabolizers, but it is not well understood whether the safety profile of intermediate metabolizers differs from that of ultrarapid and extensive metabolizers. This study compared safety and tolerability among the different CYP2D6 metabolizer groups in the 12-week open-label phase of an atomoxetine study in adult patients with ADHD. Genotyping identified 1039 patients as extensive/ultrarapid metabolizers, 780 patients as intermediate metabolizers, and 117 patients as poor metabolizers. Common (≥5% frequency) treatment-emergent adverse events did not significantly differ between extensive/ultrarapid and intermediate metabolizers (odds ratios were <2.0 or >0.5). Poor metabolizers had higher frequencies of dry mouth, erectile dysfunction, hyperhidrosis, insomnia, and urinary retention compared with the other metabolizer groups. There were no significant differences between extensive/ultrarapid and intermediate metabolizers in changes from baseline in vital signs. These results suggest that data from CYP2D6 intermediate and extensive/ultrarapid metabolizers can be combined when considering safety analyses related to atomoxetine.
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Affiliation(s)
| | | | - Si G Li
- BioStatSolutions, Inc., Frederick, MD, USA
| | - Jonna Ahl
- Eli Lilly and Company, Indianapolis, IN, USA
| | | | - Yoko Tanaka
- Eli Lilly and Company, Indianapolis, IN, USA
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Cheli S, Pietrantonio F, Clementi E, Falvella FS. LightSNiP assay is a good strategy for pharmacogenetics test. Front Pharmacol 2015; 6:114. [PMID: 26082719 PMCID: PMC4451335 DOI: 10.3389/fphar.2015.00114] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Accepted: 05/12/2015] [Indexed: 11/13/2022] Open
Affiliation(s)
- Stefania Cheli
- Unit of Clinical Pharmacology, Department of Biomedical and Clinical Sciences L. Sacco, "Luigi Sacco" University Hospital, Università di Milano Milan, Italy
| | - Filippo Pietrantonio
- Medical Oncology Department, Fondazione IRCCS Istituto Nazionale dei Tumori Milan, Italy
| | - Emilio Clementi
- Scientific Institute IRCCS Eugenio Medea Lecco, Italy ; Unit of Clinical Pharmacology, Department of Biomedical and Clinical Sciences L. Sacco, CNR Institute of Neuroscience, "Luigi Sacco" University Hospital, Università di Milano Milan, Italy
| | - Felicia S Falvella
- Unit of Clinical Pharmacology, Department of Biomedical and Clinical Sciences L. Sacco, "Luigi Sacco" University Hospital, Università di Milano Milan, Italy
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246
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Probst-Schendzielorz K, Viviani R, Stingl JC. Effect of Cytochrome P450 polymorphism on the action and metabolism of selective serotonin reuptake inhibitors. Expert Opin Drug Metab Toxicol 2015; 11:1219-32. [PMID: 26028357 DOI: 10.1517/17425255.2015.1052791] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
INTRODUCTION The aim of this article is to review the field of clinically relevant pharmacogenetic effects of cytochrome P450 polymorphisms on metabolism, kinetics, and action of selective serotonin reuptake inhibitors (SSRIs). AREAS COVERED The relevant literature in humans on the implications of genetic variation on SSRI drug exposure, drug safety, and efficacy was systematically evaluated. There is a large amount of evidence on the influences of CYP polymorphisms on the pharmacokinetics of SSRIs. Regulatory agencies have issued warnings or advice considering dose adjustments in the presence of affected metabolic phenotypes for several SSRIs. Evidence-based dose adjustments for drugs dependent on CYP genotype are available to clinicians. However, few data on the relationship between genetically determined elevated plasma concentrations of SSRIs and specific side effects or therapeutic failure are currently available. EXPERT OPINION Genetic polymorphisms in CYP2D6 and CYP2C19 exert large influences on the individual exposure to SSRIs, leading to the aim to achieve similar concentration time courses in different metabolizer phenotypes. The implementation of a stratified approach to medication with SSRIs in different metabolic phenotypes on a rational basis will require new studies assessing the association between clinical outcomes (such as adverse reactions) and genetically determined elevated plasma concentrations.
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Chaudhry AS, Prasad B, Shirasaka Y, Fohner A, Finkelstein D, Fan Y, Wang S, Wu G, Aklillu E, Sim SC, Thummel KE, Schuetz EG. The CYP2C19 Intron 2 Branch Point SNP is the Ancestral Polymorphism Contributing to the Poor Metabolizer Phenotype in Livers with CYP2C19*35 and CYP2C19*2 Alleles. Drug Metab Dispos 2015; 43:1226-35. [PMID: 26021325 DOI: 10.1124/dmd.115.064428] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 05/28/2015] [Indexed: 12/13/2022] Open
Abstract
CYP2C19 rs12769205 alters an intron 2 branch point adenine leading to an alternative mRNA in human liver with complete inclusion of intron 2 (exon 2B). rs12769205 changes the mRNA reading frame, introduces 87 amino acids, and leads to a premature stop codon. The 1000 Genomes project (http://browser.1000genomes.org/index.html) indicated rs12769205 is in linkage disequilibrium with rs4244285 on CYP2C19*2, but found alone on CYP2C19*35 in Blacks. Minigenes containing rs12769205 transfected into HepG2 cells demonstrated this single nucleotide polymorphism (SNP) alone leads to exon 2B and decreases CYP2C19 canonical mRNA. A residual amount of CYP2C19 protein was detectable by quantitative proteomics with tandem mass spectrometry in CYP2C19*2/*2 and *1/*35 liver microsomes with an exon 2 probe. However, an exon 4 probe, downstream from rs12769205, but upstream of rs4244285, failed to detect CYP2C19 protein in livers homozygous for rs12769205, demonstrating rs12769205 alone can lead to complete loss of CYP2C19 protein. CYP2C19 genotypes and mephenytoin phenotype were compared in 104 Ethiopians. Poor metabolism of mephenytoin was seen in persons homozygous for both rs12769205 and rs4244285 (CYP2C19*2/*2), but with little effect on mephenytoin disposition of CYP2C19*1/*2, CYP2C19*1/*3, or CYP2C19*1/*35 heterozygous alleles. Extended haplotype homozygosity tests of the HapMap Yorubans (YRI) showed both haplotypes carrying rs12769205 (CYP2C19*35 and CYP2C19*2) are under significant natural selection, with CYP2C19*35 having a higher relative extended haplotype homozygosity score. The phylogenetic tree of the YRI CYP2C19 haplotypes revealed rs12769205 arose first on CYP2C19*35 and that rs4244285 was added later, creating CYP2C19*2. In conclusion, rs12769205 is the ancestral polymorphism leading to aberrant splicing of CYP2C19*35 and CYP2C19*2 alleles in liver.
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Affiliation(s)
- Amarjit S Chaudhry
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee (A.S.C., E.G.S.); Department of Pharmaceutics, School of Pharmacy, University of Washington, Seattle, Washington (B.P., Y.S., A.F., K.E.T.); Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, Tennessee (D.F., Y.F., S.W., G.W.); Department of Laboratory Medicine, Division of Clinical Pharmacology, Karolinska Institutet, Stockholm, Sweden (E.A.); and Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden (S.C.S.)
| | - Bhagwat Prasad
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee (A.S.C., E.G.S.); Department of Pharmaceutics, School of Pharmacy, University of Washington, Seattle, Washington (B.P., Y.S., A.F., K.E.T.); Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, Tennessee (D.F., Y.F., S.W., G.W.); Department of Laboratory Medicine, Division of Clinical Pharmacology, Karolinska Institutet, Stockholm, Sweden (E.A.); and Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden (S.C.S.)
| | - Yoshiyuki Shirasaka
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee (A.S.C., E.G.S.); Department of Pharmaceutics, School of Pharmacy, University of Washington, Seattle, Washington (B.P., Y.S., A.F., K.E.T.); Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, Tennessee (D.F., Y.F., S.W., G.W.); Department of Laboratory Medicine, Division of Clinical Pharmacology, Karolinska Institutet, Stockholm, Sweden (E.A.); and Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden (S.C.S.)
| | - Alison Fohner
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee (A.S.C., E.G.S.); Department of Pharmaceutics, School of Pharmacy, University of Washington, Seattle, Washington (B.P., Y.S., A.F., K.E.T.); Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, Tennessee (D.F., Y.F., S.W., G.W.); Department of Laboratory Medicine, Division of Clinical Pharmacology, Karolinska Institutet, Stockholm, Sweden (E.A.); and Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden (S.C.S.)
| | - David Finkelstein
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee (A.S.C., E.G.S.); Department of Pharmaceutics, School of Pharmacy, University of Washington, Seattle, Washington (B.P., Y.S., A.F., K.E.T.); Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, Tennessee (D.F., Y.F., S.W., G.W.); Department of Laboratory Medicine, Division of Clinical Pharmacology, Karolinska Institutet, Stockholm, Sweden (E.A.); and Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden (S.C.S.)
| | - Yiping Fan
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee (A.S.C., E.G.S.); Department of Pharmaceutics, School of Pharmacy, University of Washington, Seattle, Washington (B.P., Y.S., A.F., K.E.T.); Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, Tennessee (D.F., Y.F., S.W., G.W.); Department of Laboratory Medicine, Division of Clinical Pharmacology, Karolinska Institutet, Stockholm, Sweden (E.A.); and Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden (S.C.S.)
| | - Shuoguo Wang
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee (A.S.C., E.G.S.); Department of Pharmaceutics, School of Pharmacy, University of Washington, Seattle, Washington (B.P., Y.S., A.F., K.E.T.); Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, Tennessee (D.F., Y.F., S.W., G.W.); Department of Laboratory Medicine, Division of Clinical Pharmacology, Karolinska Institutet, Stockholm, Sweden (E.A.); and Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden (S.C.S.)
| | - Gang Wu
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee (A.S.C., E.G.S.); Department of Pharmaceutics, School of Pharmacy, University of Washington, Seattle, Washington (B.P., Y.S., A.F., K.E.T.); Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, Tennessee (D.F., Y.F., S.W., G.W.); Department of Laboratory Medicine, Division of Clinical Pharmacology, Karolinska Institutet, Stockholm, Sweden (E.A.); and Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden (S.C.S.)
| | - Eleni Aklillu
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee (A.S.C., E.G.S.); Department of Pharmaceutics, School of Pharmacy, University of Washington, Seattle, Washington (B.P., Y.S., A.F., K.E.T.); Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, Tennessee (D.F., Y.F., S.W., G.W.); Department of Laboratory Medicine, Division of Clinical Pharmacology, Karolinska Institutet, Stockholm, Sweden (E.A.); and Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden (S.C.S.)
| | - Sarah C Sim
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee (A.S.C., E.G.S.); Department of Pharmaceutics, School of Pharmacy, University of Washington, Seattle, Washington (B.P., Y.S., A.F., K.E.T.); Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, Tennessee (D.F., Y.F., S.W., G.W.); Department of Laboratory Medicine, Division of Clinical Pharmacology, Karolinska Institutet, Stockholm, Sweden (E.A.); and Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden (S.C.S.)
| | - Kenneth E Thummel
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee (A.S.C., E.G.S.); Department of Pharmaceutics, School of Pharmacy, University of Washington, Seattle, Washington (B.P., Y.S., A.F., K.E.T.); Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, Tennessee (D.F., Y.F., S.W., G.W.); Department of Laboratory Medicine, Division of Clinical Pharmacology, Karolinska Institutet, Stockholm, Sweden (E.A.); and Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden (S.C.S.)
| | - Erin G Schuetz
- Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee (A.S.C., E.G.S.); Department of Pharmaceutics, School of Pharmacy, University of Washington, Seattle, Washington (B.P., Y.S., A.F., K.E.T.); Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, Tennessee (D.F., Y.F., S.W., G.W.); Department of Laboratory Medicine, Division of Clinical Pharmacology, Karolinska Institutet, Stockholm, Sweden (E.A.); and Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden (S.C.S.)
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Haufroid V, Hantson P. CYP2D6 genetic polymorphisms and their relevance for poisoning due to amfetamines, opioid analgesics and antidepressants. Clin Toxicol (Phila) 2015; 53:501-10. [DOI: 10.3109/15563650.2015.1049355] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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249
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Cytochrome P450 2D6 genotype affects the pharmacokinetics of controlled-release paroxetine in healthy Chinese subjects: comparison of traditional phenotype and activity score systems. Eur J Clin Pharmacol 2015; 71:835-41. [DOI: 10.1007/s00228-015-1855-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 04/27/2015] [Indexed: 10/23/2022]
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250
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Gaedigk A, Garcia-Ribera C, Jeong HE, Shin JG, Hernandez-Sanchez J, Hernandez-Sanchez JT. Resolution of a clinical AmpliChip CYP450 Test™ no call: discovery and characterization of novel CYP2D6*1 haplotypes. Pharmacogenomics 2015; 15:1175-84. [PMID: 25141893 DOI: 10.2217/pgs.14.94] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
A Han Chinese patient failed CYP2D6 genotype analysis with the AmpliChip CYP450 Test™. The CYP2D6 gene locus of the patient and her son were extensively genotyped including copy number variation and gene resequencing. Two SNPs were discovered on the patient's CYP2D6*1 allele, -498C>A and 1661G>C, while the son's CYP2D6*1 allele had -498C>A only. AmpliChip failure was attributed to the presence of a CYP2D6*1 allele carrying the 1661G>C SNP. Functional analyses of -498C>A did not reveal altered activity in vitro or in vivo suggesting that both novel CYP2D6*1 subvariants are functional. The implementation of pharmacogenetics-guided drug therapy relies on accurate clinical-grade genotype analysis. Although the AmpliChip is a reliable platform, numerous allelic (sub)variants and gene arrangements are not detected or may trigger no calls. While such cases may be rare, the clinical/genetic testing community must be aware of the challenges of CYP2D6 testing on the AmpliChip platform and implications regarding accuracy of test results.
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Affiliation(s)
- Andrea Gaedigk
- Division of Clinical Pharmacology, Toxicology & Therapeutic Innovation, Children's Mercy Hospital, 2401 Gilham Road, Kansas City, MO 64108, USA
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