1
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Turner AJ, Nofziger C, Ramey BE, Ly RC, Bousman CA, Agúndez JAG, Sangkuhl K, Whirl-Carrillo M, Vanoni S, Dunnenberger HM, Ruano G, Kennedy MA, Phillips MS, Hachad H, Klein TE, Moyer AM, Gaedigk A. PharmVar Tutorial on CYP2D6 Structural Variation Testing and Recommendations on Reporting. Clin Pharmacol Ther 2023; 114:1220-1237. [PMID: 37669183 PMCID: PMC10840842 DOI: 10.1002/cpt.3044] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 08/23/2023] [Indexed: 09/07/2023]
Abstract
The Pharmacogene Variation Consortium (PharmVar) provides nomenclature for the highly polymorphic human CYP2D6 gene locus and a comprehensive summary of structural variation. CYP2D6 contributes to the metabolism of numerous drugs and, thus, genetic variation in its gene impacts drug efficacy and safety. To accurately predict a patient's CYP2D6 phenotype, testing must include structural variants including gene deletions, duplications, hybrid genes, and combinations thereof. This tutorial offers a comprehensive overview of CYP2D6 structural variation, terms, and definitions, a review of methods suitable for their detection and characterization, and practical examples to address the lack of standards to describe CYP2D6 structural variants or any other pharmacogene. This PharmVar tutorial offers practical guidance on how to detect the many, often complex, structural variants, as well as recommends terms and definitions for clinical and research reporting. Uniform reporting is not only essential for electronic health record-keeping but also for accurate translation of a patient's genotype into phenotype which is typically utilized to guide drug therapy.
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Affiliation(s)
- Amy J Turner
- Department of Pediatrics, Children’s Research Institute, The Medical College of Wisconsin, Milwaukee, Wisconsin, USA
- RPRD Diagnostics LLC, Wauwatosa, Wisconsin, USA
| | | | | | - Reynold C Ly
- Department of Medical and Molecular Genetics, Division of Diagnostic Genomics, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Chad A Bousman
- Department of Medical Genetics, University of Calgary, Calgary, Alberta, Canada
| | - José AG Agúndez
- University of Extremadura, Cáceres, Spain
- Institute of Molecular Pathology Biomarkers, Cáceres, Spain
| | - Katrin Sangkuhl
- Department of Biomedical Data Science, Stanford University, Stanford, California, USA
| | | | | | - Henry M Dunnenberger
- Mark R. Neaman Center for Personalized Medicine, NorthShore University Health System, Evanston, Illinois, USA
| | - Gualberto Ruano
- Institute of Living, Hartford Hospital (Hartford CT) and Department of Psychiatry, University of Connecticut School of Medicine (Farmington CT), USA
| | - Martin A Kennedy
- Department of Pathology and Biomedical Science, University of Otago, Christchurch, New Zealand
| | | | - Houda Hachad
- Houda Hachad, Department of Clinical Operations, AccessDx Laboratories, Houston, Texas, USA
| | - Teri E Klein
- Departments of Biomedical Data Science and Medicine (BMIR), Stanford University, Stanford, California, USA
| | - Ann M Moyer
- Division of Laboratory Genetics and Genomics, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | - Andrea Gaedigk
- Children’s Mercy Research Institute (CMRI), Kansas City, Missouri, USA
- School of Medicine, University of Missouri-Kansas City, Kansas City, Missouri, USA
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2
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Carvalho Henriques B, Buchner A, Hu X, Wang Y, Yavorskyy V, Wallace K, Dong R, Martens K, Carr MS, Behroozi Asl B, Hague J, Sivapalan S, Maier W, Dernovsek MZ, Henigsberg N, Hauser J, Souery D, Cattaneo A, Mors O, Rietschel M, Pfeffer G, Hume S, Aitchison KJ. Methodology for clinical genotyping of CYP2D6 and CYP2C19. Transl Psychiatry 2021; 11:596. [PMID: 34811360 PMCID: PMC8608805 DOI: 10.1038/s41398-021-01717-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 10/28/2021] [Indexed: 01/10/2023] Open
Abstract
Many antidepressants, atomoxetine, and several antipsychotics are metabolized by the cytochrome P450 enzymes CYP2D6 and CYP2C19, and guidelines for prescribers based on genetic variants exist. Although some laboratories offer such testing, there is no consensus regarding validated methodology for clinical genotyping of CYP2D6 and CYP2C19. The aim of this paper was to cross-validate multiple technologies for genotyping CYP2D6 and CYP2C19 against each other, and to contribute to feasibility for clinical implementation by providing an enhanced range of assay options, customizable automated translation of data into haplotypes, and a workflow algorithm. AmpliChip CYP450 and some TaqMan single nucleotide variant (SNV) and copy number variant (CNV) data in the Genome-based therapeutic drugs for depression (GENDEP) study were used to select 95 samples (out of 853) to represent as broad a range of CYP2D6 and CYP2C19 genotypes as possible. These 95 included a larger range of CYP2D6 hybrid configurations than have previously been reported using inter-technology data. Genotyping techniques employed were: further TaqMan CNV and SNV assays, xTAGv3 Luminex CYP2D6 and CYP2C19, PharmacoScan, the Ion AmpliSeq Pharmacogenomics Panel, and, for samples with CYP2D6 hybrid configurations, long-range polymerase chain reactions (L-PCRs) with Sanger sequencing and Luminex. Agena MassARRAY was also used for CYP2C19. This study has led to the development of a broader range of TaqMan SNV assays, haplotype phasing methodology with TaqMan adaptable for other technologies, a multiplex genotyping method for efficient identification of some hybrid haplotypes, a customizable automated translation of SNV and CNV data into haplotypes, and a clinical workflow algorithm.
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Affiliation(s)
| | - Avery Buchner
- grid.17089.370000 0001 2190 316XDepartment of Psychiatry, University of Alberta, Edmonton, Canada ,grid.17089.370000 0001 2190 316XNeuroscience and Mental Health Institute, University of Alberta, Edmonton, Canada
| | - Xiuying Hu
- grid.17089.370000 0001 2190 316XDepartment of Psychiatry, University of Alberta, Edmonton, Canada
| | - Yabing Wang
- grid.17089.370000 0001 2190 316XDepartment of Psychiatry, University of Alberta, Edmonton, Canada
| | - Vasyl Yavorskyy
- grid.17089.370000 0001 2190 316XDepartment of Psychiatry, University of Alberta, Edmonton, Canada ,grid.17089.370000 0001 2190 316XDepartment of Biological Sciences, University of Alberta, Edmonton, Canada
| | - Keanna Wallace
- grid.17089.370000 0001 2190 316XDepartment of Psychiatry, University of Alberta, Edmonton, Canada
| | - Rachael Dong
- grid.17089.370000 0001 2190 316XNeuroscience and Mental Health Institute, University of Alberta, Edmonton, Canada
| | - Kristina Martens
- grid.22072.350000 0004 1936 7697Department of Clinical Neurosciences, Cumming School of Medicine, Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
| | - Michael S. Carr
- grid.17089.370000 0001 2190 316XDepartment of Psychiatry, University of Alberta, Edmonton, Canada ,grid.17089.370000 0001 2190 316XDepartment of Pharmacology, University of Alberta, Edmonton, Canada
| | - Bahareh Behroozi Asl
- grid.17089.370000 0001 2190 316XDepartment of Psychiatry, University of Alberta, Edmonton, Canada ,grid.17089.370000 0001 2190 316XNeuroscience and Mental Health Institute, University of Alberta, Edmonton, Canada
| | - Joshua Hague
- grid.17089.370000 0001 2190 316XDepartment of Psychiatry, University of Alberta, Edmonton, Canada ,grid.17089.370000 0001 2190 316XDepartment of Medical Genetics, University of Alberta, Edmonton, Canada
| | - Sudhakar Sivapalan
- grid.17089.370000 0001 2190 316XDepartment of Psychiatry, University of Alberta, Edmonton, Canada
| | - Wolfgang Maier
- grid.10388.320000 0001 2240 3300Department of Psychiatry and Psychotherapy, University of Bonn, Bonn, Germany
| | | | - Neven Henigsberg
- grid.4808.40000 0001 0657 4636Croatian Institute for Brain Research, Centre for Excellence for Basic, Clinical and Translational Research, University of Zagreb School of Medicine, Zagreb, Croatia
| | - Joanna Hauser
- grid.22254.330000 0001 2205 0971Departnent of Psychiatry, Poznan University of Medical Sciences, Poznań, Poland
| | - Daniel Souery
- grid.4989.c0000 0001 2348 0746Laboratoire de Psychologie Médicale, Université Libre de Bruxelles and Psy Pluriel, Centre Européen de Psychologie Médicale, Brussels, Belgium
| | - Annamaria Cattaneo
- grid.419422.8Biological Psychiatry Unit, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy ,grid.4708.b0000 0004 1757 2822Department of Pharmacological and Biomolecular Sciences, University of Milan, via Balzaretti 9, 20133 Milan, Italy
| | - Ole Mors
- grid.154185.c0000 0004 0512 597XPsychosis Research Unit, Aarhus University Hospital, Risskov, Denmark
| | - Marcella Rietschel
- grid.7700.00000 0001 2190 4373Department of Genetic Epidemiology in Psychiatry, Central Institute of Mental Health, Medical Faculty of Mannheim, Heidelberg University, Mannheim, Germany
| | - Gerald Pfeffer
- grid.22072.350000 0004 1936 7697Department of Clinical Neurosciences, Cumming School of Medicine, Hotchkiss Brain Institute, University of Calgary, Calgary, Canada ,grid.22072.350000 0004 1936 7697Alberta Child Health Research Institute & Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, Canada
| | - Stacey Hume
- grid.17089.370000 0001 2190 316XDepartment of Medical Genetics, University of Alberta, Edmonton, Canada ,Alberta Precision Laboratories, Edmonton, Canada
| | - Katherine J. Aitchison
- grid.17089.370000 0001 2190 316XDepartment of Psychiatry, University of Alberta, Edmonton, Canada ,grid.17089.370000 0001 2190 316XNeuroscience and Mental Health Institute, University of Alberta, Edmonton, Canada ,grid.17089.370000 0001 2190 316XDepartment of Medical Genetics, University of Alberta, Edmonton, Canada ,grid.413574.00000 0001 0693 8815Alberta Health Services, Edmonton, Canada ,grid.13097.3c0000 0001 2322 6764King’s College London, London, UK
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Manoharan A, Shewade DG, Ravindranath PA, Rajkumar RP, Ramprasad VL, Adithan S, Damodaran SE. Resequencing CYP2D6 gene in Indian population: CYP2D6*41 identified as the major reduced function allele. Pharmacogenomics 2019; 20:719-729. [PMID: 31368850 DOI: 10.2217/pgs-2019-0049] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Aim: The CYP2D6 gene is highly polymorphic and harbors population specific alleles that define its predominant metabolizer phenotype. This study aimed to identify polymorphisms in Indian population owing to scarcity of CYP2D6 data in this population. Materials & methods: The CYP2D6 gene was resequenced in 105 south Indians using next generation sequencing technology and haplotypes were reconstructed. Results & conclusion: Four novel missense variants have been designated as CYP2D6*110, *111, *112 and *113. The most common alleles were CYP2D6*1 (42%), *2 (32%), and *41 (12.3%) and diplotypes were CYP2D6*1/*2 (26%), *1/*1 (11%), *2/*41 (10%) and *1/*41 (7%) accounting for high incidence of extensive metabolizers in Indians.
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Affiliation(s)
- Aarthi Manoharan
- Department of Pharmacology, Jawaharlal Institute of Postgraduate Medical Education & Research, Puducherry 605006, India
| | - Deepak Gopal Shewade
- Department of Pharmacology, Jawaharlal Institute of Postgraduate Medical Education & Research, Puducherry 605006, India
| | | | - Ravi Philip Rajkumar
- Department of Psychiatry, Jawaharlal Institute of Postgraduate Medical Education & Research, Puducherry 605006, India
| | | | - Surendiran Adithan
- Department of Pharmacology, Jawaharlal Institute of Postgraduate Medical Education & Research, Puducherry 605006, India
| | - Solai Elango Damodaran
- Department of Pharmacology, Jawaharlal Institute of Postgraduate Medical Education & Research, Puducherry 605006, India
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4
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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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5
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Yasukochi Y, Satta Y. Molecular evolution of the CYP2D subfamily in primates: purifying selection on substrate recognition sites without the frequent or long-tract gene conversion. Genome Biol Evol 2015; 7:1053-67. [PMID: 25808902 PMCID: PMC4419802 DOI: 10.1093/gbe/evv056] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/18/2015] [Indexed: 01/21/2023] Open
Abstract
The human cytochrome P450 (CYP) 2D6 gene is a member of the CYP2D gene subfamily, along with the CYP2D7P and CYP2D8P pseudogenes. Although the CYP2D6 enzyme has been studied extensively because of its clinical importance, the evolution of the CYP2D subfamily has not yet been fully understood. Therefore, the goal of this study was to reveal the evolutionary process of the human drug metabolic system. Here, we investigate molecular evolution of the CYP2D subfamily in primates by comparing 14 CYP2D sequences from humans to New World monkey genomes. Window analysis and statistical tests revealed that entire genomic sequences of paralogous genes were extensively homogenized by gene conversion during molecular evolution of CYP2D genes in primates. A neighbor-joining tree based on genomic sequences at the nonsubstrate recognition sites showed that CYP2D6 and CYP2D8 genes were clustered together due to gene conversion. In contrast, a phylogenetic tree using amino acid sequences at substrate recognition sites did not cluster the CYP2D6 and CYP2D8 genes, suggesting that the functional constraint on substrate specificity is one of the causes for purifying selection at the substrate recognition sites. Our results suggest that the CYP2D gene subfamily in primates has evolved to maintain the regioselectivity for a substrate hydroxylation activity between individual enzymes, even though extensive gene conversion has occurred across CYP2D coding sequences.
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Affiliation(s)
- Yoshiki Yasukochi
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-0033 Japan
| | - Yoko Satta
- Department of Evolutionary Studies of Biosystems, The Graduate University for Advanced Studies, Shonan Village, Hayama, Kanagawa, 240-0193 Japan
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6
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Riccardi LN, Lanzellotto R, Falconi M, Ceccardi S, Bini C, Pelotti S. Development of a tetraplex PCR assay for CYP2D6 genotyping in degraded DNA samples. J Forensic Sci 2013; 59:690-5. [PMID: 24313823 DOI: 10.1111/1556-4029.12358] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Revised: 01/28/2013] [Accepted: 02/09/2013] [Indexed: 11/26/2022]
Abstract
CYP2D6 polymorphism analysis is gaining increasing interest in forensic pharmacogenetics. Nevertheless, DNA recovered from forensic samples could be of poor quality and not suitable for long polymerase chain reaction required to type CYP2D6 gene prior to SNaPshot minisequencing analysis performed to define alleles with different enzymatic activity. We developed and validated following the guidelines of the Scientific Working Group on DNA Analysis Methods a tetraplex PCR yielding four amplicons of 597, 803, 1142, and 1659 bp encompassing the entire CYP2D6 gene to analyze eleven SNP positions by SNaPshot minisequencing. Concordance, sensitivity, and specificity were assessed. The method, applied to thirty-two forensic samples failed to amplify with long PCR, allowed the amplification of CYP2D6 gene in 62.5% of degraded samples. The new tetraplex PCR appears a suitable method for CYP2D6 analysis in forensic pharmacogenetics.
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Affiliation(s)
- Laura N Riccardi
- Department of Medical and Surgical Sciences, Institute of Legal Medicine, University of Bologna, via Irnerio, 49, 40126, Bologna, Italy
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7
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Abstract
Cytochrome P450 2D6 (CYP2D6) plays an important role in the metabolism and bioactivation of about 25% of clinically used drugs including many antidepressants, antipsychotics and opioids. CYP2D6 activity is highly variably ranging from no activity in so-called poor metabolizers to ultrarapid metabolism at the other end of the extreme of the activity distribution. A large portion of this variability can be explained by the highly polymorphic nature of the CYP2D6 gene locus for which > 100 variants and subvariants identified to date. Allele frequencies vary markedly between ethnic groups; some have exclusively or predominantly only been observed in certain populations. Pharmacogenetic testing holds the promise of individualizing drug therapy by identifying patients with CYP2D6 diplotypes that puts them at an increased risk of experiencing dose-related adverse events or therapeutic failure. Inferring a patient's CYP2D6 metabolic capacity, or phenotype, however, is a challenging task due to the complexity of the CYP2D6 gene locus. Allelic variation includes SNPs, small insertions and deletions, gene copy number variation and rearrangements with CYP2D7, a highly related non-functional gene. This review provides a summary of the intricacies of CYP2D6 variation and genotype analysis, knowledge that is invaluable for the translation of genotype into clinically useful information.
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Affiliation(s)
- Andrea Gaedigk
- Children's Mercy Hospital and Clinics, Division of Clinical Pharmacology and Innovative Therapeutics , Kansas City, Missouri , USA
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8
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9
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Gaedigk A, Jaime LKM, Bertino JS, Bérard A, Pratt VM, Bradfordand LD, Leeder JS. Identification of Novel CYP2D7-2D6 Hybrids: Non-Functional and Functional Variants. Front Pharmacol 2010; 1:121. [PMID: 21833166 PMCID: PMC3153001 DOI: 10.3389/fphar.2010.00121] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2010] [Accepted: 09/02/2010] [Indexed: 01/12/2023] Open
Abstract
Polymorphic expression of CYP2D6 contributes to the wide range of activity observed for this clinically important drug metabolizing enzyme. In this report we describe novel CYP2D7/2D6 hybrid genes encoding non-functional and functional CYP2D6 protein and a CYP2D7 variant that mimics a CYP2D7/2D6 hybrid gene. Five-kilobyte-long PCR products encompassing the novel genes were entirely sequenced. A quantitative assay probing in different gene regions was employed to determine CYP2D6 and 2D7 copy number variations and the relative position of the hybrid genes within the locus was assessed by long-range PCR. In addition to the previously known CYP2D6*13 and *66 hybrids, we describe three novel non-functional CYP2D7-2D6 hybrids with gene switching in exon 2 (CYP2D6*79), intron 2 (CYP2D6*80), and intron 5 (CYP2D6*67). A CYP2D7-specific T-ins in exon 1 causes a detrimental frame shift. One subject revealed a CYP2D7 conversion in the 5'-flanking region of a CYP2D6*35 allele, was otherwise unaffected (designated CYP2D6*35B). Finally, three DNAs revealed a CYP2D7 gene with a CYP2D6-like region downstream of exon 9 (designated CYP2D7[REP6]). Quantitative copy number determination, sequence analyses, and long-range PCR mapping were in agreement and excluded the presence of additional gene units. Undetected hybrid genes may cause over-estimation of CYP2D6 activity (CYP2D6*1/*1 vs *1/hybrid, etc), but may also cause results that may interfere with the genotype determination. Detection of hybrid events, "single" and tandem, will contribute to more accurate phenotype prediction from genotype data.
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Affiliation(s)
- Andrea Gaedigk
- Division of Developmental Pharmacology and Experimental Therapeutics, The Children's Mercy Hospital and Clinics Kansas City, MO, USA
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10
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Seripa D, Pilotto A, Panza F, Matera MG, Pilotto A. Pharmacogenetics of cytochrome P450 (CYP) in the elderly. Ageing Res Rev 2010; 9:457-74. [PMID: 20601196 DOI: 10.1016/j.arr.2010.06.001] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2010] [Revised: 05/28/2010] [Accepted: 06/01/2010] [Indexed: 12/22/2022]
Abstract
The genetics of cytochrome P450 (CYP) is a very active area of multidisciplinary research, overlapping the interest of medicine, biology and pharmacology, being the CYP enzyme system responsible for the metabolism of more than 80% of the commercially available drugs. Variations in CYP encoding genes are responsible for inter-individual differences in CYP production or function, with severe clinical consequences as therapeutic failures (TFs) and adverse drug reactions (ADRs), being ADRs worldwide primary causes of morbidity and mortality in elderly people. In fact, the prevalence of both TFs and ADRs strongly increased in the presence of multiple pharmacological treatments, a common status in subjects aging 65 years and over. The present article explored some basic concepts of human genetics that have important implications in the genetics of CYP. An attempted to transfer these basic concepts to the genetic data reported by the Home Page of The Human Cytochrome P450 (CYP) Allele Nomenclature Committee was also made, focusing on the current knowledge of CYP genetics. The status of what we know and what we need to know is the base for the clinical applications of pharmacogenetics, in which personalized drug treatments constituted the main aim, in particular in patients attending a geriatric ward.
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Affiliation(s)
- Davide Seripa
- Geriatric Unit & Gerontology-Geriatrics Research Laboratory, Department of Medical Sciences, IRCCS Casa Sollievo della Sofferenza, Viale Cappuccini 1, 71013 San Giovanni Rotondo (FG), Italy.
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11
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Gaedigk A, Fuhr U, Johnson C, Bérard LA, Bradford D, Leeder JS. CYP2D7-2D6 hybrid tandems: identification of novel CYP2D6 duplication arrangements and implications for phenotype prediction. Pharmacogenomics 2010; 11:43-53. [PMID: 20017671 DOI: 10.2217/pgs.09.133] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
AIMS Allelic variants of cytochrome P450 CYP2D6 (CYP2D6), such as gene deletion, duplication, multiplication and conversion, contribute to the wide range of CYP2D6 activity. Novel gene arrangements were discovered and characterized. MATERIALS & METHODS DNA from 32 Caucasian and 59 African-American duplication-positive subjects were analyzed by long-range PCR and genotyping to detect CYP2D7-2D6 hybrid tandem alleles. Novel allelic variants were sequenced and a strategy for the detection and analysis of hybrid genes was refined. RESULTS CYP2D7-2D6 hybrid tandem alleles were identified in one African-American and four Caucasian subjects. Three novel hybrid genes were found on CYP2D6*1 and CYP2D6*2 duplication backgrounds and designated CYP2D6*76, *77 and *78. CYP2D7 to 2D6 conversion occurred in introns 1 and 4, and exon 9. All carried a T-insertion in exon 1 abolishing activity. In Caucasians, four out of 33 (12%) of the duplication-positive alleles were hybrid tandems, three CYP2D6*77 + *2 and one CYP2D6*78 + *2. By contrast, in African-Americans only one of 60 duplication-positive alleles was identified as a hybrid tandem. This allele was designated CYP2D6*76 + *1. CONCLUSION Hybrid tandem alleles occur infrequently (<0.25%) in Caucasians, but may explain why not every subject with a CYP2D6 duplication presents with an ultrarapid metabolizer phenotype.
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Affiliation(s)
- Andrea Gaedigk
- Section of Developmental Pharmacology & Experimental Therapeutics, The Children's Mercy Hospital and Clinics, 2401 Gillham Road, Kansas City, MO 62108, USA.
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12
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Abstract
OBJECTIVE CYP2D6 is a polymorphic gene. It has been observed to be deleted, to be duplicated and to undergo recombination events involving the CYP2D7 pseudogene and surrounding sequences. The objective of this study was to discover the genomic structure of CYP2D6 recombinants that interfere with clinical genotyping platforms that are available today. METHODS Clinical samples containing rare homozygous CYP2D6 alleles, ambiguous readouts, and those with duplication signals and two different alleles were analyzed by long-range PCR amplification of individual genes, PCR fragment analysis, allele-specific primer extension assay, and DNA sequencing to characterize alleles and genomic structure. RESULTS Novel alleles, genomic structures, and the DNA sequence of these structures are described. Interestingly, in 49 of 50 DNA samples that had CYP2D6 gene duplications or multiplications where two alleles were detected, the chromosome containing the duplication or multiplication had identical tandem alleles. CONCLUSION Several new CYP2D6 alleles and genomic structures are described which will be useful for CYP2D6 genotyping. The findings suggest that the recombination events responsible for CYP2D6 duplications and multiplications are because of mechanisms other than interchromosomal crossover during meiosis.
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Affiliation(s)
- Shu-Feng Zhou
- Discipline of Chinese Medicine, School of Health Sciences, RMIT University, Victoria, Australia.
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14
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Zhou SF, Liu JP, Chowbay B. Polymorphism of human cytochrome P450 enzymes and its clinical impact. Drug Metab Rev 2009; 41:89-295. [PMID: 19514967 DOI: 10.1080/03602530902843483] [Citation(s) in RCA: 502] [Impact Index Per Article: 33.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Pharmacogenetics is the study of how interindividual variations in the DNA sequence of specific genes affect drug response. This article highlights current pharmacogenetic knowledge on important human drug-metabolizing cytochrome P450s (CYPs) to understand the large interindividual variability in drug clearance and responses in clinical practice. The human CYP superfamily contains 57 functional genes and 58 pseudogenes, with members of the 1, 2, and 3 families playing an important role in the metabolism of therapeutic drugs, other xenobiotics, and some endogenous compounds. Polymorphisms in the CYP family may have had the most impact on the fate of therapeutic drugs. CYP2D6, 2C19, and 2C9 polymorphisms account for the most frequent variations in phase I metabolism of drugs, since almost 80% of drugs in use today are metabolized by these enzymes. Approximately 5-14% of Caucasians, 0-5% Africans, and 0-1% of Asians lack CYP2D6 activity, and these individuals are known as poor metabolizers. CYP2C9 is another clinically significant enzyme that demonstrates multiple genetic variants with a potentially functional impact on the efficacy and adverse effects of drugs that are mainly eliminated by this enzyme. Studies into the CYP2C9 polymorphism have highlighted the importance of the CYP2C9*2 and *3 alleles. Extensive polymorphism also occurs in other CYP genes, such as CYP1A1, 2A6, 2A13, 2C8, 3A4, and 3A5. Since several of these CYPs (e.g., CYP1A1 and 1A2) play a role in the bioactivation of many procarcinogens, polymorphisms of these enzymes may contribute to the variable susceptibility to carcinogenesis. The distribution of the common variant alleles of CYP genes varies among different ethnic populations. Pharmacogenetics has the potential to achieve optimal quality use of medicines, and to improve the efficacy and safety of both prospective and currently available drugs. Further studies are warranted to explore the gene-dose, gene-concentration, and gene-response relationships for these important drug-metabolizing CYPs.
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Affiliation(s)
- Shu-Feng Zhou
- School of Health Sciences, RMIT University, Bundoora, Victoria, Australia.
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The CYP2D6 gene locus in South African Coloureds: unique allele distributions, novel alleles and gene arrangements. Eur J Clin Pharmacol 2008; 64:465-75. [DOI: 10.1007/s00228-007-0445-7] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2007] [Accepted: 12/08/2007] [Indexed: 01/26/2023]
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Rotger M, Saumoy M, Zhang K, Flepp M, Sahli R, Decosterd L, Telenti A. Partial deletion of CYP2B6 owing to unequal crossover with CYP2B7. Pharmacogenet Genomics 2007; 17:885-90. [PMID: 17885627 DOI: 10.1097/fpc.0b013e3282ef5cd1] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVE To evaluate the possibility of copy number variation (CNV) of CYP2B6. METHODS We investigated CNV in 226 HIV-1-infected individuals by quantitative PCR. Identification of a candidate CNV prompted characterization of the size of deletion by assessment of absence of exons, mapping of the recombination site by sequencing, and by southern blot. The functional consequences of CNV were assessed in silico (predicted protein), and in vivo, by evaluation of plasma drug levels of the CYP2B6 substrate efavirenz. RESULTS Analyses identified one white individual carrying a heterozygous deletion of exons 1-4 of CYP2B6. We identified a approximately 68 kb deletion between CYP2B7 and CYP2B6, and mapped the crossover to a homologous region in intron 4 of both genes. The new hybrid allele, named CYP2B6*29, carries two amino acid substitutions, Q172H and M198T, previously associated with impaired enzyme function. Consistent with the functional prediction, the average of efavirenz area under the curve values of the patient was mean+/-SD, 81.64+/-23.62, versus 47.75+/-19.73 mug h/ml for individuals with an extensive metabolizer phenotype. CONCLUSION CYP2B6*29 represents a new mechanism of genetic variation at the CYP2B6 locus, underscoring the highly polymorphic nature of this isoenzyme.
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Affiliation(s)
- Margalida Rotger
- Institute of Microbiology, University Hospital Center and University of Lausanne, Lausanne; Switzerland
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Gaedigk A, Ndjountché L, Divakaran K, Dianne Bradford L, Zineh I, Oberlander TF, Brousseau DC, McCarver DG, Johnson JA, Alander SW, Wayne Riggs K, Steven Leeder J. Cytochrome P4502D6 (CYP2D6) Gene Locus Heterogeneity: Characterization of Gene Duplication Events. Clin Pharmacol Ther 2007; 81:242-51. [PMID: 17259947 DOI: 10.1038/sj.clpt.6100033] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Duplications and multiplications of active CYP2D6 genes can cause ultrarapid drug metabolism and lead to therapeutic failure. Multiple functional and non-functional duplication alleles have been further characterized. Duplications were detected by long-range polymerase chain reaction (PCR), PCR-restriction fragment length polymorphism, and sequence analysis. A PCR fragment encompassing the entire duplicated gene was utilized for detailed characterization. Duplications occurred at 1.3, 5.75, and 2.0% in Caucasian, African American, and racially mixed populations, respectively (n=887 total). Of those 28, 47, and 17% were non-functional CYP2D6*4 x N. Twelve unique duplication alleles were detected: *1 x N, *2 x N, *4 x N, *6 x N, *10 x N, *17 x N, *17 x N[spacer], *29 x N, *35 x N, *43 x N, *45 x N, and a novel non-functional tandem arrangement of a chimeric 2D7/2D6 and *1 gene. All novel duplications except *35 x N were found in African Americans. Accurate identification of gene duplication events is essential to avoid false-positive ultrarapid metabolism assignments and thus, overestimation of predicted activity and increased risk for unwanted adverse events.
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Affiliation(s)
- A Gaedigk
- Section of Developmental Pharmacology & Experimental Therapeutics, The Children's Mercy Hospital and Clinics, Kansas City, Missouri, USA.
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Fukuda T, Maune H, Ikenaga Y, Naohara M, Fukuda K, Azuma J. Novel structure of the CYP2D6 gene that confuses genotyping for the CYP2D6*5 allele. Drug Metab Pharmacokinet 2006; 20:345-50. [PMID: 16272752 DOI: 10.2133/dmpk.20.345] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We encountered DNA samples which showed a positive product using a long PCR-based method for the detection of CYP2D6*5, indicating deletion of the entire CYP2D6 gene, but the samples did not show a band related to CYP2D6*5 in either XbaI- or EcoRI-RFLP analysis. To achieve genotyping with accuracy, we performed a further genetic analysis to clarify the discrepancy. An unknown 1.6-kb insert was identified in a region downstream from the CYP2D6 stop codon where a specific primer was designed for long-PCR analysis for CYP2D6*5 genotyping. This finding suggested that the CYP2D6 gene might not be deleted in the samples even if a positive product was detected by the long-PCR method. Furthermore, the allelic frequency of this type was found to be approximately 0.3% (4 heterozygous/771 samples) in a Japanese population. In conclusion, we found a novel structure of the CYP2D6 gene, which might lead to incorrect genotyping for CYP2D6*5. Although the long PCR-based strategy for the detection of CYP2D6*5 has been widely used due to its usefulness and convenience, we recommend caution when adopting this method and propose re-evaluating the method for detecting CYP2D6*5.
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Affiliation(s)
- Tsuyoshi Fukuda
- Clinical Evaluation of Medicines and Therapeutics, Graduate School of Pharmaceutical Sciences, Osaka University, Yamada-oka, Osaka, Japan
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Nagata K, Yamazoe Y. Genetic Polymorphism of Human Cytochrome P450 Involved in Drug Metabolism. Drug Metab Pharmacokinet 2002; 17:167-89. [PMID: 15618668 DOI: 10.2133/dmpk.17.167] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Recent advances in human gene analysis promoted by the human genome project have brought us a massive amount of information. These data can be seen and analyzed by personal computer through individual Web sites. As a result, the best use of bioinformatic is essential for recent molecular biology research. Genetic polymorphism of drug-metabolizing enzymes influences individual drug efficacy and safety through the alteration of pharmacokinetics and disposition of drugs. Considerable amounts of data have now accumulated as allelic differences of various drug metabolizing enzymes. Current understanding of genotype information on cytochrome P450 is hereby summarized, based on the Web site for their use in individual optimization of drug therapy.
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Affiliation(s)
- Kiyoshi Nagata
- Department of Drug Metabolism and Molecular Toxicology, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan.
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Løvlie R, Daly AK, Matre GE, Molven A, Steen VM. Polymorphisms in CYP2D6 duplication-negative individuals with the ultrarapid metabolizer phenotype: a role for the CYP2D6*35 allele in ultrarapid metabolism? PHARMACOGENETICS 2001; 11:45-55. [PMID: 11207030 DOI: 10.1097/00008571-200102000-00006] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Ultrarapid drug metabolism mediated by CYP2D6 is associated with inheritance of alleles with duplicated or amplified functional CYP2D6 genes. However, genotyping for duplicated CYP2D6 alleles only explains a fraction (10-30%) of the ultrarapid metabolizer phenotypes observed in Caucasian populations. Using a sample of CYP2D6 duplication-negative ultrarapid metabolizer subjects and selected control subjects with extensive metabolism, we examined parts of the CYP2D7 pseudogene, and the promoter region and 5'-coding sequence of CYP2D6 for polymorphisms possibly associated with the ultrarapid metabolizer phenotype. In an initial screening of 17 subjects (13 ultrarapid metabolizers and four extensive metabolizers), we identified three DNA variants in the 5'-end of the CYP2D7 pseudogene and 29 variants in the 5'-end of the CYP2D6 gene. Five variants were then selected for examination in a larger sample of subjects having the ultrarapid metabolizer (n = 27) or extensive metabolizer phenotype (n = 77). Subsequent statistical analyses of allele, genotype and estimated haplotype distributions showed that the 31A allele of the 31G > A (Val(II)Met) polymorphism was significantly more frequent in ultrarapid metabolizer subjects than in extensive metabolizer subjects (P = 0.04). Also, estimation of haplotype frequencies suggested that one of the haplotypes with the 31A variant was significantly more frequent among the ultrarapid metabolizers compared with the extensive metabolizers (P = 0.03). The average metabolic ratio was significantly lower in subjects possessing the 31A allele compared with subjects homozygous for the 31G allele (P = 0.02). We also observed a nonsignificant over-representation of the G-allele of a - 1584 C > G promoter polymorphism in the ultrarapid metabolizer group. Since our results are based on a relatively low number of subjects, further studies on larger samples and functional analyses of the polymorphisms detected are necessary to determine the role of the 31G > A and - 1584C > 6 variants in CYP2D6 duplication-negative ultrarapid metabolizer subjects.
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Affiliation(s)
- R Løvlie
- Dr Einar Martens Research Group for Biological Psychiatry, Haukeland University Hospital and University of Bergen, Norway.
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Wormhoudt LW, Commandeur JN, Vermeulen NP. Genetic polymorphisms of human N-acetyltransferase, cytochrome P450, glutathione-S-transferase, and epoxide hydrolase enzymes: relevance to xenobiotic metabolism and toxicity. Crit Rev Toxicol 1999; 29:59-124. [PMID: 10066160 DOI: 10.1080/10408449991349186] [Citation(s) in RCA: 217] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
In this review, an overview is presented of the current knowledge of genetic polymorphisms of four of the most important enzyme families involved in the metabolism of xenobiotics, that is, the N-acetyltransferase (NAT), cytochrome P450 (P450), glutathione-S-transferase (GST), and microsomal epoxide hydrolase (mEH) enzymes. The emphasis is on two main topics, the molecular genetics of the polymorphisms and the consequences for xenobiotic metabolism and toxicity. Studies are described in which wild-type and mutant alleles of biotransformation enzymes have been expressed in heterologous systems to study the molecular genetics and the metabolism and pharmacological or toxicological effects of xenobiotics. Furthermore, studies are described that have investigated the effects of genetic polymorphisms of biotransformation enzymes on the metabolism of drugs in humans and on the metabolism of genotoxic compounds in vivo as well. The effects of the polymorphisms are highly dependent on the enzyme systems involved and the compounds being metabolized. Several polymorphisms are described that also clearly influence the metabolism and effects of drugs and toxic compounds, in vivo in humans. Future perspectives in studies on genetic polymorphisms of biotransformation enzymes are also discussed. It is concluded that genetic polymorphisms of biotransformation enzymes are in a number of cases a major factor involved in the interindividual variability in xenobiotic metabolism and toxicity. This may lead to interindividual variability in efficacy of drugs and disease susceptibility.
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Affiliation(s)
- L W Wormhoudt
- Leiden Amsterdam Center for Drug Research, Vrije Universiteit, Department of Pharmacochemistry, The Netherlands
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Wan J, Imaoka S, Chow T, Hiroi T, Yabusaki Y, Funae Y. Expression of four rat CYP2D isoforms in Saccharomyces cerevisiae and their catalytic specificity. Arch Biochem Biophys 1997; 348:383-90. [PMID: 9434752 DOI: 10.1006/abbi.1997.0402] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We cloned four cDNAs belonging to the CYP2D subfamily to express these enzymes in yeast cells and to compare their catalytic activities simultaneously. Three are believed to be alleles of CYP2D1, 2D2, and 2D3, respectively, based on high nucleotide sequence similarity, while CYP2D4 had both sequences of CYP2D4 and CYP2D18. Expression plasmids carrying CYP2D cDNAs were transformed into Saccharomyces cerevisiae. Typical P450 CO-difference spectra with absorbance maximum at 448 nm were recorded with microsomal preparations from the yeast cells expressing the four CYP2D forms. A catalytic study of these CYP2D forms was done with debrisoquine, bufuralol, and lidocaine. CYP2D2 had the highest debrisoquine 4-hydroxylation (2.2 nmol/min/nmol P450) activity, similar to that (2.2 nmol/min/nmol) of human CYP2D6 expressed in yeast cells. CYP2D3 had high lidocaine N-deethylation (43 nmol/min/nmol P450) activity, and both CYP2D3 and 2D2 exhibited high lidocaine 3-hydroxylation (2.4 and 1.6 nmol/min/nmol P450, respectively) activity. Bufuralol 1'-hydroxylation catalytic capabilities were comparable among the four isoforms. The activity of CYP2D1 was relatively low toward the three substrates (debrisoquine, 0.091; bufuralol, 1.5; lidocaine 3-hydroxylation, 0.019; lidocaine N-deethylation, 2.8 nmol/min/nmol P450). These findings indicate that debrisoquine, a typical substrate for CYP2D forms, was mainly metabolized by CYP2D2 but not CYP2D1 in rat liver and that the CYP2D forms have different substrate specificity.
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Affiliation(s)
- J Wan
- Laboratory of Chemistry, Osaka City University Medical School, Japan
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Sachse C, Brockmöller J, Bauer S, Roots I. Cytochrome P450 2D6 variants in a Caucasian population: allele frequencies and phenotypic consequences. Am J Hum Genet 1997; 60:284-95. [PMID: 9012401 PMCID: PMC1712396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Cytochrome P450 2D6 (CYP2D6) metabolizes many important drugs. CYP2D6 activity ranges from complete deficiency to ultrafast metabolism, depending on at least 16 different known alleles. Their frequencies were determined in 589 unrelated German volunteers and correlated with enzyme activity measured by phenotyping with dextromethorphan or debrisoquine. For genotyping, nested PCR-RFLP tests from a PCR amplificate of the entire CYP2D6 gene were developed. The frequency of the CYP2D6*1 allele coding for extensive metabolizer (EM) phenotype was .364. The alleles coding for slightly (CYP2D6*2) or moderately (*9 and *10) reduced activity (intermediate metabolizer phenotype [IM]) showed frequencies of .324, .018, and .015, respectively. By use of novel PCR tests for discrimination, CYP2D6 gene duplication alleles were found with frequencies of .005 (*1x2), .013 (*2x2), and .001 (*4x2). Frequencies of alleles with complete deficiency (poor metabolizer phenotype [PM]) were .207 (*4), .020 (*3 and *5), .009 (*6), and .001 (*7, *15, and *16). The defective CYP2D6 alleles *8, *11, *12, *13, and *14 were not found. All 41 PMs (7.0%) in this sample were explained by five mutations detected by four PCR-RFLP tests, which may suffice, together with the gene duplication test, for clinical prediction of CYP2D6 capacity. Three novel variants of known CYP2D6 alleles were discovered: *1C (T1957C), *2B (additional C2558T), and *4E (additional C2938T). Analysis of variance showed significant differences in enzymatic activity measured by the dextromethorphan metabolic ratio (MR) between carriers of EM/PM (mean MR = .006) and IM/PM (mean MR = .014) alleles and between carriers of one (mean MR = .009) and two (mean MR = .003) functional alleles. The results of this study provide a solid basis for prediction of CYP2D6 capacity, as required in drug research and routine drug treatment.
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Affiliation(s)
- C Sachse
- Institute of Clinical Pharmacology, University Clinic Charité, Humboldt University of Berlin, Germany
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