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Pharmacogenomic analysis of a genetically distinct Indigenous population. THE PHARMACOGENOMICS JOURNAL 2022; 22:100-108. [PMID: 34824386 DOI: 10.1038/s41397-021-00262-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 11/08/2021] [Accepted: 11/10/2021] [Indexed: 11/09/2022]
Abstract
Indigenous Australians face a disproportionately severe burden of chronic disease relative to other Australians, with elevated rates of morbidity and mortality. While genomics technologies are slowly gaining momentum in personalised treatments for many, a lack of pharmacogenomic research in Indigenous peoples could delay adoption. Appropriately implementing pharmacogenomics in clinical care necessitates an understanding of the frequencies of pharmacologically relevant genetic variants within Indigenous populations. We analysed whole-genome sequence data from 187 individuals from the Tiwi Islands and characterised the pharmacogenomic landscape of this population. Specifically, we compared variant profiles and allelic distributions of previously described pharmacologically significant genes and variants with other population groups. We identified 22 translationally relevant pharmacogenomic variants and 18 clinically actionable guidelines with implications for drug dosing and treatment of conditions including heart disease, diabetes and cancer. We specifically observed increased poor and intermediate metabolizer phenotypes in the CYP2C9 (PM:19%, IM:44%) and CYP2C19 (PM:18%, IM:44%) genes.
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2
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Gebremichael LG, Suppiah V, Wiese MD, Mackenzie L, Phillips C, Williams DB, Roberts MS. Efficacy and safety of statins in ethnic differences: a lesson for application in Indigenous Australian patient care. Pharmacogenomics 2021; 22:553-571. [PMID: 34120458 DOI: 10.2217/pgs-2020-0152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Although statins are effective in treating high cholesterol, adverse effects do occur with their use. Efficacy and tolerability vary among statins in different ethnic groups. Indigenous Australians have a high risk for cardiovascular and kidney diseases. Prescribing statins to Indigenous Australians with multi-morbidity requires different strategies to increase efficacy and reduce their toxicity. Previous studies have reported that Indigenous Australians are more susceptible to severe statin-induced myopathies. However, there is a lack of evidence in the underlying genetic factors in this population. This review aims to identify: inter-ethnic differences in the efficacy and safety of statins; major contributing factors accounting for any identified differences; and provide an overview of statin-induced adverse effects in Indigenous Australians.
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Affiliation(s)
- Lemlem G Gebremichael
- UniSA Clinical & Health Science, University of South Australia, Adelaide, SA 5000, Australia
| | - Vijayaprakash Suppiah
- UniSA Clinical & Health Science, University of South Australia, Adelaide, SA 5000, Australia.,Australian Centre for Precision Health, University of South Australia, Adelaide, SA 5000, Australia
| | - Michael D Wiese
- UniSA Clinical & Health Science, University of South Australia, Adelaide, SA 5000, Australia
| | - Lorraine Mackenzie
- UniSA Clinical & Health Science, University of South Australia, Adelaide, SA 5000, Australia
| | - Craig Phillips
- UniSA Clinical & Health Science, University of South Australia, Adelaide, SA 5000, Australia
| | - Desmond B Williams
- UniSA Clinical & Health Science, University of South Australia, Adelaide, SA 5000, Australia
| | - Michael S Roberts
- UniSA Clinical & Health Science, University of South Australia, Adelaide, SA 5000, Australia.,Therapeutics Research Centre, Diamantina Institute, The University of Queensland, Translational Research Institute, Woolloongabba, QLD 4102, Australia.,Basil Hetzel Institute for Translational Medical Research, The Queen Elizabeth Hospital, 28 Woodville Rd, Woodville, SA 5011, Australia
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3
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Suarez-Kurtz G, Aklillu E, Saito Y, Somogyi AA. Conference report: pharmacogenomics in special populations at WCP2018. Br J Clin Pharmacol 2019; 85:467-475. [PMID: 30537134 DOI: 10.1111/bcp.13828] [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] [Received: 10/08/2018] [Revised: 11/19/2018] [Accepted: 11/21/2018] [Indexed: 12/12/2022] Open
Abstract
The 18th World Congress of Basic and Clinical Pharmacology (WCP2018), coordinated by IUPHAR and hosted by the Japanese Pharmacological Society and the Japanese Society of Clinical Pharmacology and Therapeutics, was held in July 2018 at the Kyoto International Conference Center, in Kyoto, Japan. Having as its main theme 'Pharmacology for the Future: Science, Drug Development and Therapeutics', WCP2018 was attended by over 4500 delegates, representing 78 countries. The present report is an overview of a symposium at WCP2018, entitled Pharmacogenomics in Special Populations, organized by IUPHAR´s Pharmacogenetics/Genomics (PGx) section. The PGx section congregates distinguished scientists from different continents, covering expertise from basic research, to clinical implementation and ethical aspects of PGx, and one of its major activities is the coordination of symposia and workshops to foster exchange of PGx knowledge (https://iuphar.org/sections-subcoms/pharmacogenetics-genomics/). The symposium attracted a large audience to listen to presentations covering various areas of research and clinical adoption of PGx in Oceania, Africa, Latin America and Asia.
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Affiliation(s)
| | - Eleni Aklillu
- Division of Clinical Pharmacology, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Yoshiro Saito
- Division of Medical Safety Science, National Institute of Health Sciences, Kawasaki, Japan
| | - Andrew A Somogyi
- Discipline of Pharmacology, Adelaide Medical School, University of Adelaide, Adelaide, Australia
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Yu CY, Ang GY, Subramaniam V, Johari James R, Ahmad A, Abdul Rahman T, Mohd Nor F, Shaari SA, Teh LK, Salleh MZ. Inference of the Genetic Polymorphisms of CYP2D6 in Six Subtribes of the Malaysian Orang Asli from Whole-Genome Sequencing Data. Genet Test Mol Biomarkers 2017; 21:409-415. [PMID: 28525288 DOI: 10.1089/gtmb.2016.0235] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
AIMS CYP2D6 is one of the major enzymes in the cytochrome P450 monooxygenase system. It metabolizes ∼25% of prescribed drugs and hence, the genetic diversity of a CYP2D6 gene has continued to be of great interest to the medical and pharmaceutical industries. This study was designed to perform a systematic analysis of the CYP2D6 gene in six subtribes of the Malaysian Orang Asli. METHODS Genomic DNAs were extracted from the blood samples followed by whole-genome sequencing. The reads were aligned to the reference human genome hg19 and variants in the CYP2D6 gene were analyzed. CYP2D6*5 and duplication of CYP2D6 were analyzed using previously established methods. RESULTS A total of 72 single nucleotide polymorphisms were identified. CYP2D6*1, *2, *4, *5, *10,*41, and duplication of the gene were found in the Orang Asli, whereby CYP2D6*2 and *41 alleles are reported for the first time in the Malaysian population. CONCLUSION The findings in this study provide insights into the genetic polymorphisms of CYP2D6 in the Orang Asli of Peninsular Malaysia.
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Affiliation(s)
- Choo Yee Yu
- 1 Integrative Pharmacogenomics Institute (iPROMISE), Universiti Teknologi MARA (UiTM) , Puncak Alam, Malaysia
| | - Geik Yong Ang
- 1 Integrative Pharmacogenomics Institute (iPROMISE), Universiti Teknologi MARA (UiTM) , Puncak Alam, Malaysia
| | - Vinothini Subramaniam
- 1 Integrative Pharmacogenomics Institute (iPROMISE), Universiti Teknologi MARA (UiTM) , Puncak Alam, Malaysia
| | - Richard Johari James
- 1 Integrative Pharmacogenomics Institute (iPROMISE), Universiti Teknologi MARA (UiTM) , Puncak Alam, Malaysia .,2 Faculty of Pharmacy, Universiti Teknologi MARA (UiTM) , Sungai Buloh, Malaysia
| | - Aminuddin Ahmad
- 3 Faculty of Medicine, Universiti Teknologi MARA (UiTM) , Sungai Buloh, Malaysia
| | | | - Fadzilah Mohd Nor
- 3 Faculty of Medicine, Universiti Teknologi MARA (UiTM) , Sungai Buloh, Malaysia
| | - Syahrul Azlin Shaari
- 3 Faculty of Medicine, Universiti Teknologi MARA (UiTM) , Sungai Buloh, Malaysia
| | - Lay Kek Teh
- 1 Integrative Pharmacogenomics Institute (iPROMISE), Universiti Teknologi MARA (UiTM) , Puncak Alam, Malaysia .,2 Faculty of Pharmacy, Universiti Teknologi MARA (UiTM) , Sungai Buloh, Malaysia
| | - Mohd Zaki Salleh
- 1 Integrative Pharmacogenomics Institute (iPROMISE), Universiti Teknologi MARA (UiTM) , Puncak Alam, Malaysia .,2 Faculty of Pharmacy, Universiti Teknologi MARA (UiTM) , Sungai Buloh, Malaysia
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Total and unbound ceftriaxone pharmacokinetics in critically ill Australian Indigenous patients with severe sepsis. Int J Antimicrob Agents 2016; 48:748-752. [PMID: 27838278 DOI: 10.1016/j.ijantimicag.2016.09.021] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 09/04/2016] [Accepted: 09/15/2016] [Indexed: 11/21/2022]
Abstract
In the absence of specific data to guide optimal dosing, this study aimed to describe the pharmacokinetics of ceftriaxone in severely septic Australian Indigenous patients and to assess achievement of the pharmacodynamic target of the regimens prescribed. A pharmacokinetic study was conducted in a remote hospital intensive care unit in patients receiving ceftriaxone dosing of 1 g every 12 h (q12h). Serial blood and urine samples were collected over one dosing interval on two consecutive days. Samples were assayed using a validated chromatography method for total and unbound concentrations. Concentration-time data collected were analysed with a non-compartmental approach. A total of 100 plasma samples were collected from five subjects. Ceftriaxone clearance, volume of distribution at steady-state, elimination half-life and elimination rate constant estimates were 0.9 (0.6-1.5) L/h, 11.2 (7.6-13.4) L, 9.5 (3.2-10.2) h and 0.07 (0.07-0.21) h-1, respectively. The unbound fraction of ceftriaxone ranged between 14% and 43%, with a higher unbound fraction present at higher total concentrations. The unbound concentrations at 720 min from the initiation of infusion for the first and second dosing intervals were 7.2 (4.8-10.7) mg/L and 7.8 (4.7-12.1) mg/L respectively, which exceeds the minimum inhibitory concentration of all typical target pathogens. In conclusion, the regimen of ceftriaxone 1 g q12h is adequate for critically ill Australian Indigenous patients with severe sepsis caused by non-resistant pathogens.
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Tsai D, Stewart P, Goud R, Gourley S, Hewagama S, Krishnaswamy S, Wallis SC, Lipman J, Roberts JA. Optimising meropenem dosing in critically ill Australian Indigenous patients with severe sepsis. Int J Antimicrob Agents 2016; 48:542-546. [PMID: 27771187 DOI: 10.1016/j.ijantimicag.2016.08.015] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Revised: 08/03/2016] [Accepted: 08/09/2016] [Indexed: 12/12/2022]
Abstract
Currently there are no pharmacokinetic (PK) data to guide antibiotic dosing in critically ill Australian Indigenous patients with severe sepsis. This study aimed to determine whether the population pharmacokinetics of meropenem were different between critically ill Australian Indigenous and critically ill Caucasian patients. Serial plasma and urine samples as well as clinical and demographic data were collected over two dosing intervals from critically ill Australian Indigenous patients. Plasma meropenem concentrations were assayed by validated chromatography. Concentration-time data were analysed with data from a previous PK study in critically ill Caucasian patients using Pmetrics. The population PK model was subsequently used for Monte Carlo dosing simulations to describe optimal doses for these patients. Six Indigenous and five Caucasian subjects were included. A two-compartment model described the data adequately, with meropenem clearance and volume of distribution of the central compartment described by creatinine clearance (CLCr) and patient weight, respectively. Patient ethnicity was not supported as a covariate in the final model. Significant differences were observed for meropenem clearance between the Indigenous and Caucasian groups [median 11.0 (range 3.0-14.1) L/h vs. 17.4 (4.3-30.3) L/h, respectively; P <0.01]. Standard dosing regimens (1 g intravenous every 8 h as a 30-min infusion) consistently achieved target exposures at the minimum inhibitory concentration breakpoint in the absence of augmented renal clearance. No significant interethnic differences in meropenem pharmacokinetics between the Indigenous and Caucasian groups were detected and CLCr was found to be the strongest determinant of appropriate dosing regimens.
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Affiliation(s)
- Danny Tsai
- Burns, Trauma and Critical Care Research Centre, School of Medicine, The University of Queensland, Brisbane, Queensland, Australia; Department of Intensive Care Medicine, Alice Springs Hospital, Alice Springs, Northern Territory, Australia; Pharmacy Department, Alice Springs Hospital, Alice Springs, Northern Territory, Australia.
| | - Penelope Stewart
- Department of Intensive Care Medicine, Alice Springs Hospital, Alice Springs, Northern Territory, Australia
| | - Rajendra Goud
- Department of Intensive Care Medicine, Alice Springs Hospital, Alice Springs, Northern Territory, Australia
| | - Stephen Gourley
- Emergency Department, Alice Springs Hospital, Alice Springs, Northern Territory, Australia
| | - Saliya Hewagama
- Department of Medicine, Alice Springs Hospital, Alice Springs, Northern Territory, Australia; Department of Infectious Diseases, The Northern Hospital, Epping, Melbourne, Victoria, Australia
| | - Sushena Krishnaswamy
- Department of Medicine, Alice Springs Hospital, Alice Springs, Northern Territory, Australia; Monash Infectious Diseases, Monash Health, Clayton, Melbourne, Victoria, Australia
| | - Steven C Wallis
- Burns, Trauma and Critical Care Research Centre, School of Medicine, The University of Queensland, Brisbane, Queensland, Australia
| | - Jeffrey Lipman
- Burns, Trauma and Critical Care Research Centre, School of Medicine, The University of Queensland, Brisbane, Queensland, Australia; Department of Intensive Care Medicine, The Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia
| | - Jason A Roberts
- Burns, Trauma and Critical Care Research Centre, School of Medicine, The University of Queensland, Brisbane, Queensland, Australia; Department of Intensive Care Medicine, The Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia
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7
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Helsby NA. CYP2C19 and CYP2D6 genotypes in Pacific peoples. Br J Clin Pharmacol 2016; 82:1303-1307. [PMID: 27304207 DOI: 10.1111/bcp.13045] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 06/10/2016] [Accepted: 06/14/2016] [Indexed: 01/08/2023] Open
Abstract
The study of pharmacogenetic variants in populations which reside in Oceania has been focused mainly on CYP2C19 and CYP2D6. Statements about the high prevalence of CYP2C19 no function genotype in 'Pacific Islanders' can be found in the literature. This review article summarizes the published information about these pharmacogenes in this geographical region and highlights the differences observed between Melanesian and Polynesian populations. It is not appropriate to combine the prevalence data of pharmacogenetic variants, particularly CYP2C19, across this region. Indeed, apocryphal assumptions about CYP2C19 no function alleles and possible effect on the therapeutic activity of clopidogrel are unhelpful and reiterate the importance of assessing the individual patient rather than relying on inappropriate ethnicity-based assumptions for drug dosing decisions.
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Affiliation(s)
- Nuala A Helsby
- School of Medical Sciences, University of Auckland, New Zealand.
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Naranjo MEG, de Andrés F, Delgado A, Cobaleda J, Peñas-Lledó EM, LLerena A. High frequency of CYP2D6 ultrarapid metabolizers in Spain: controversy about their misclassification in worldwide population studies. THE PHARMACOGENOMICS JOURNAL 2016; 16:485-90. [PMID: 27272044 DOI: 10.1038/tpj.2016.47] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 03/14/2016] [Accepted: 05/02/2016] [Indexed: 02/06/2023]
Abstract
A high frequency (7-10%) of CYP2D6 ultrarapid metabolizers estimated from the genotype (gUMs) has been claimed to exist among Spaniards and Southern Europeans. However, methodological aspects such as the inclusion of individuals carrying non-active multiplied alleles as gUMs may have led to an overestimation. Thus, this study aimed to analyze the gUM frequency (considering only those carrying more than two active genes) in 805 Spanish healthy volunteers studied for CYP2D6*2, *3, *4, *5, *6, *10, *17, *35, *41, and multiplications. Second, all worldwide studies reporting gUM frequencies were reviewed in order to evaluate potential misclassifications. The gUM frequency in this Spanish population was 5.34%, but increased to 8.3% if all individuals with CYP2D6 multiplications were classified as gUMs without considering the activity of the multiplied alleles. Moreover, among all reviewed worldwide studies only 55.6% precisely determined whether the multiplied alleles were active. Present results suggest that the evaluation of CYP2D6 ultrarapid metabolism should be standarized, and that the frequency of gUMs should be reconsidered in Spaniards and globally.
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Affiliation(s)
- M E G Naranjo
- CICAB Clinical Research Center, Extremadura University and Medical School, Badajoz, Spain
| | - F de Andrés
- CICAB Clinical Research Center, Extremadura University and Medical School, Badajoz, Spain
| | - A Delgado
- CICAB Clinical Research Center, Extremadura University and Medical School, Badajoz, Spain
| | - J Cobaleda
- CICAB Clinical Research Center, Extremadura University and Medical School, Badajoz, Spain.,Primary Health Care Center 'Ciudad Jardín', Badajoz, Spain
| | - E M Peñas-Lledó
- CICAB Clinical Research Center, Extremadura University and Medical School, Badajoz, Spain
| | - A LLerena
- CICAB Clinical Research Center, Extremadura University and Medical School, Badajoz, Spain.,CIBERSAM, Instituto de Salud Carlos III, Madrid, Spain
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Hu XX, Zhou Q, Lan T, Huang XX, Liang BQ, Dai DP, Cai JP, Hu GX. Functional characterization of 22 novel CYP2D6 variants for the metabolism of Tamoxifen. ACTA ACUST UNITED AC 2016; 68:819-25. [PMID: 27109434 DOI: 10.1111/jphp.12556] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Accepted: 03/13/2016] [Indexed: 11/29/2022]
Abstract
OBJECTIVES This study aimed to assess the catalytic characteristics of 24 CYP2D6 allelic isoforms found in Chinese Han population on the metabolism of tamoxifen in vitro. METHODS Recombinant CYP2D6 microsomes of distinguished genotypes were used to characterize the corresponding enzyme activity towards tamoxifen. About 5-2500 μm tamoxifen was incubated for 30 min at 37 °C. Using high-performance liquid chromatography to detect the products, the kinetic parameters Km , Vmax and intrinsic clearance (Vmax /Km ) of N-desmethyltamoxifen were determined. KEY FINDINGS Of the 24 tested allelic variants, the differences of intrinsic clearance value were shown as follows: CYP2D6.89 was much higher than wild-type CYP2D6.1, 2 allelic isoforms (CYP2D6.88 and D336N) exhibited similar intrinsic clearance values as the wild-type enzyme, two variants displayed weak or no activity, while the rest 19 variants showed significantly reduced intrinsic clearance values ranging from 7.46 to 81.11%. CONCLUSION The comprehensive assessment of CYP2D6 variants provides significant insights into allele-specific activity towards tamoxifen in vitro, suggesting that most of the carriers of these alleles might be paid more attention when using CYP2D6-mediated drugs clinically.
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Affiliation(s)
- Xiao-Xia Hu
- Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Quan Zhou
- Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Tian Lan
- Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xiang-Xin Huang
- Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Bing-Qing Liang
- Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Da-Peng Dai
- The Key Laboratory of Geriatrics, Beijing Hospital & Beijing Institute of Geriatrics Ministry of Health, Beijing, China
| | - Jian-Ping Cai
- The Key Laboratory of Geriatrics, Beijing Hospital & Beijing Institute of Geriatrics Ministry of Health, Beijing, China
| | - Guo-Xin Hu
- Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China
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Hu XX, Yuan LJ, Fang P, Mao YH, Zhan YY, Li XY, Dai DP, Cai JP, Hu GX. Effect of CYP2D6 genetic polymorphism on the metabolism of citalopram in vitro. Drug Metab Pharmacokinet 2016; 31:133-8. [PMID: 27016952 DOI: 10.1016/j.dmpk.2016.01.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Revised: 12/21/2015] [Accepted: 01/14/2016] [Indexed: 12/17/2022]
Abstract
Genetic polymorphisms of CYP2D6 significantly influence the efficacy and safety of some drugs, which might cause adverse effects and therapeutic failure. We aimed at investigating the role of CYP2D6 in the metabolism of citalopram and identifying the effect of 24 CYP2D6 allelic variants we found in Chinese Han population on the metabolism of citalopram in vitro. These CYP2D6 variants expressed by insect cells system were incubated with 10-1000 μM citalopram for 30 min at 37 °C and the reaction was terminated by cooling to -80 °C immediately. Citalopram and its metabolites were analyzed by high-performance liquid chromatography (HPLC). The intrinsic clearance (Vmax/Km) values of the variants toward citalopram metabolites were significantly altered, 38-129% for demethylcitalopram and 13-138% for citalopram N-oxide when compared with CYP2D6*1. Most of the tested rare alleles exhibited significantly decreased values due to increased Km and/or decreased Vmax values. We conclude that recombinant system could be used to investigate the enzymes involved in drug metabolism and these findings suggest that more attention should be paid to subjects carrying these CYP2D6 alleles when administering citalopram in the clinic.
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Affiliation(s)
- Xiao-Xia Hu
- Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Ling-Jing Yuan
- Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Ping Fang
- Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Yong-Hui Mao
- Department of Nephrology, Beijing Hospital, Ministry of Health, Beijing, China
| | - Yun-Yun Zhan
- Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xiang-Yu Li
- Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Da-Peng Dai
- The Key Laboratory of Geriatrics, Beijing Hospital, Beijing Institute of Geriatrics, Ministry of Health, Beijing, China
| | - Jian-Ping Cai
- The Key Laboratory of Geriatrics, Beijing Hospital, Beijing Institute of Geriatrics, Ministry of Health, Beijing, China.
| | - Guo-Xin Hu
- Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China.
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Jin T, Zhang M, Yang H, Geng T, Zhang N, Feng T, Ma Y, Yuan D, Kang L. Genetic polymorphisms of the drug-metabolizing enzymeCYP2C19in the Uyghur population in northwest China. Xenobiotica 2015; 46:634-640. [DOI: 10.3109/00498254.2015.1102986] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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12
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Interethnic variation of CYP2C19 alleles, 'predicted' phenotypes and 'measured' metabolic phenotypes across world populations. THE PHARMACOGENOMICS JOURNAL 2015; 16:113-23. [PMID: 26503820 DOI: 10.1038/tpj.2015.70] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 07/15/2015] [Accepted: 08/19/2015] [Indexed: 02/08/2023]
Abstract
The present study evaluates the worldwide frequency distribution of CYP2C19 alleles and CYP2C19 metabolic phenotypes ('predicted' from genotypes and 'measured' with a probe drug) among healthy volunteers from different ethnic groups and geographic regions, as well as the relationship between the 'predicted' and 'measured' CYP2C19 metabolic phenotypes. A total of 52 181 healthy volunteers were studied within 138 selected original research papers. CYP2C19*17 was 42- and 24-fold more frequent in Mediterranean-South Europeans and Middle Easterns than in East Asians (P<0.001, in both cases). Contrarily, CYP2C19*2 and CYP2C19*3 alleles were more frequent in East Asians (30.26% and 6.89%, respectively), and even a twofold higher frequency of these alleles was found in Native populations from Oceania (61.30% and 14.42%, respectively; P<0.001, in all cases), which may be a consequence of genetic drift process in the Pacific Islands. Regarding CYP2C19 metabolic phenotype, poor metabolizers (PMs) were more frequent among Asians than in Europeans, contrarily to the phenomenon reported for CYP2D6. A correlation has been found between the frequencies of CYP2C19 poor metabolism 'predicted' from CYP2C19 genotypes (gPMs) and the poor metabolic phenotype 'measured' with a probe drug (mPMs) when subjects are either classified by ethnicity (r=0.94, P<0.001) or geographic region (r=0.99, P=0.002). Nevertheless, further research is needed in African and Asian populations, which are under-represented, and additional CYP2C19 variants and the 'measured' phenotype should be studied.
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LLerena A, Naranjo MEG, Rodrigues-Soares F, Penas-LLedó EM, Fariñas H, Tarazona-Santos E. Interethnic variability ofCYP2D6alleles and of predicted and measured metabolic phenotypes across world populations. Expert Opin Drug Metab Toxicol 2014; 10:1569-83. [DOI: 10.1517/17425255.2014.964204] [Citation(s) in RCA: 112] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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14
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Gulati S, Yadav A, Kumar N, Kumar G, Aggarwal N, Gupta R. Frequency distribution of high risk alleles of CYP2C19, CYP2E1, CYP3A4 genes in Haryana population. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2014; 37:1186-1193. [PMID: 24814262 DOI: 10.1016/j.etap.2014.03.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Revised: 03/12/2014] [Accepted: 03/16/2014] [Indexed: 06/03/2023]
Abstract
The genotype of an individual can significantly influence the disposition of a chemical, and determine their susceptibility to its toxicity. Many enzymes involved in either activation or detoxification of chemical carcinogen metabolism are polymorphically expressed, with the alleles presenting different enzymatic activities and some of them having been associated with susceptibility to cancer. Cytochrome P450 (P450 or CYP) constitutes the most important phase I enzyme group responsible for the metabolism of endogenous and exogenous (xenobiotics) substances. The present study was aimed to analyze the frequencies of commonly known polymorphisms of human xenobiotic metabolizing genes (XMG) in the Haryana State population of North India. The study was conducted in 308 healthy Haryana volunteers. DNA was extracted from leucocytes and the genetic polymorphisms in CYP2C19*2, CYP2C19*3, CYP2E1*5B and CYP3A4*1B were determined by digesting the PCR Product with restriction enzymes BamHI, SmaI, PstI and PstI respectively. The genotype frequencies of CYP2C19*2, CYP2C19*3, CYP2E1*5B, and CYP3A4*1B were found to be 22.0%, 0.0%, 2.11% and 2.0% respectively. The North Indian population which is known to be Caucasoid Aryans is ethnically different from South Indians known as Caucasoid Dravidians but no significant difference in genetic polymorphism was found.
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Affiliation(s)
- Sachin Gulati
- Department of Biotechnology, Kurukshetra University, Kurukshetra (Haryana) 136119, India.
| | - Anita Yadav
- Department of Biotechnology, Kurukshetra University, Kurukshetra (Haryana) 136119, India.
| | - Neeraj Kumar
- Department of Biotechnology, Kurukshetra University, Kurukshetra (Haryana) 136119, India.
| | - Gaurav Kumar
- Department of Biochemistry, Kurukshetra University, Kurukshetra (Haryana) 136119, India.
| | - Neeraj Aggarwal
- Department of Microbiology, Kurukshetra University, Kurukshetra (Haryana) 136119, India.
| | - Ranjan Gupta
- Department of Biochemistry, Kurukshetra University, Kurukshetra (Haryana) 136119, India.
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Tharanga TDP, Jinadasa CMV, Risama MF, Galappatthy P, Jayakody RL, Dissanayake VHW. Genetic variants in the cytochrome P450 2D6 gene in the Sri Lankan population. INDIAN JOURNAL OF HUMAN GENETICS 2014; 19:392-6. [PMID: 24497701 PMCID: PMC3897131 DOI: 10.4103/0971-6866.124361] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
INTRODUCTION: Cytochrome P450 2D6 (CYP2D6) enzymes are involved in the metabolism of a large number of commonly prescribed drugs such as antidepressants and cardiovascular drugs. The CYP2D6 *3, *4 and *14 variants associated with the loss of enzyme function; CYP2D6 *10 and *17 variants with reduced enzyme function; and CYP2D6 *2 variant with no effect on enzyme function. Establishing the frequency of these variant alleles in Sri Lankan population would be useful for optimizing pharmacotherapy with CYP2D6-substrate drugs. OBJECTIVE: The objective of this study was to determine the prevalence of CYP2D6 *2, *3, *4, *10, *14 and *17 variants in the main ethnic groups in the Sri Lankan population. MATERIALS AND METHODS: A total of 90 deoxyribonucleic acid (DNA) samples (30 each from Sinhalese, Tamils and Moors) were selected from a DNA resource at the Human Genetic Unit, Faculty of Medicine, University of Colombo. This collection had been made for population genetic studies from a random population based volunteers. Genotyping was performed using published polymerase chain reaction/restriction fragment length polymorphism methods. RESULTS: The prevalence of the CYP2D6 variants in Sinhalese, Sri Lankan Tamils and Moors respectively were CYP2D6 *2: 37%, 41.6% and 37.9%; CYP2D6 *3: 60.3%, 45% and 30%; CYP2D6 *4: 21.6%, 6.6% and 8.3%; CYP2D6 *10: 40%, 35% and 44%. CYP2D6 *14 and *17 variants were not identified. CONCLUSION: CYP2D6*3, *4 and *10 variants, which are associated with reduced or loss of CYP2D6 enzyme function were found in our population in significant frequencies. CYP2D6*4, which is reported to be a Caucasian variant was also found in all three ethnic groups.
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Affiliation(s)
- T D Praveen Tharanga
- Department of Pharmacology, Faculty of Medicine, University of Colombo, Colombo 00800, Sri Lanka
| | - C M V Jinadasa
- Department of Human Genetics Unit, Faculty of Medicine, University of Colombo, Colombo 00800, Sri Lanka
| | - M F Risama
- Department of Human Genetics Unit, Faculty of Medicine, University of Colombo, Colombo 00800, Sri Lanka
| | | | - R L Jayakody
- Department of Pharmacology, Faculty of Medicine, University of Colombo, Colombo 00800, Sri Lanka
| | - Vajira H W Dissanayake
- Department of Human Genetics Unit, Faculty of Medicine, University of Colombo, Colombo 00800, Sri Lanka
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Tabari RG, Marjani A, Ataby OA, Mansourian AR, Samai NM. Genetic Polymorphism of Cytochrome p450 (2C19) Enzyme in Iranian Turkman Ethnic Group. Oman Med J 2013; 28:237-44. [PMID: 23904915 DOI: 10.5001/omj.2013.69] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Accepted: 05/28/2013] [Indexed: 01/01/2023] Open
Abstract
OBJECTIVE Different findings indicate that CYP2C plays a clinical role in determining interindividual and interethnic differences in drug effectiveness. The ethnic differences in the frequency of CYP2C19 mutant alleles continue to be a significant study topic. The aim of the present study was to assess the frequency of allelic variants of CYP2C19 in Turkman ethnic groups and compare them with the frequencies in other ethnic populations. METHODS The study group included 140 unrelated healthy ethnic Turkman subject referred to the Health Center. Genotyping of CYP2C19 alleles (CYP2C19*1, CYP2C19*2, and CYP2C19*3 alleles) was carried out by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism technique. RESULTS The allele frequency of CYP2C19*1, CYP2C19*2 and CYP2C19*3 were 56.43%, 23.57% and 20%, respectively. The result also showed that 39.7% of subjects expressed the CYP2C19*1/*1 genotype. While 42.1%, 9.3%, 9.3% and 1.4% expressed CYP2C19*1/*2, CYP2C19*1/*3, CYP2C19*2/*2 and CYP2C19*3/*3 genotypes, respectively. The genotype CYP2C19*2/*3 was not expressed in this study population. The findings suggested that 10% of subjects were poor metabolizers by expressing CYP2C19*2/*2 and CYP2C19*3/*3 genotypes. Fifty one percent of subjects were intermediate metabolizers having CYP2C19*1/*2, CYP2C19*2/*3 and CYP2C19*1/*3 genotypes and 37.86% were found to be extensive metabolizers expressing CYP2C19*1/*1 genotype. The frequency of intermediate metabolizers genotype was high (51%) in Turkman ethnic groups. CONCLUSION This study showed that the determined allelic variants of CYP2C19 (CYP2C19*2 and CYP2C19*3 mutations) in Turkman ethnic group are comparable to other populations. These findings could be useful for the clinicians in different country to determine optimal dosage and effectiveness of drugs metabolized by this polymorphic enzyme.
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Affiliation(s)
- Robabeh Ghiyas Tabari
- Department of Biochemistry and Biophysics, Metabolic Disorders Research Center, Gorgan Faculty of Medicine, Golestan University of Medical Sciences, Gorgan, Golestan province, Iran
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Sipeky C, Weber A, Szabo M, Melegh BI, Janicsek I, Tarlos G, Szabo I, Sumegi K, Melegh B. High prevalence of CYP2C19*2 allele in Roma samples: study on Roma and Hungarian population samples with review of the literature. Mol Biol Rep 2013; 40:4727-35. [PMID: 23645039 DOI: 10.1007/s11033-013-2569-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Accepted: 04/29/2013] [Indexed: 12/22/2022]
Abstract
The purpose of our study was to characterise the CYP2C19*2 and CYP2C19*3 alleles in healthy Roma and Hungarian populations. DNA of 500 Roma and 370 Hungarian subjects were genotyped for CYP2C19*2 (G681A, rs4244285) and CYP2C19*3 (G636A, rs4986893) by PCR-RFLP assay and direct sequencing. Significant differences were found comparing the Roma and Hungarian populations in CYP2C19 681 GG (63.6 vs. 75.9%), GA (31.8 vs. 23.0%), AA (4.6 vs. 1.1%), GA+AA (36.4 vs. 24.1%) and A allele frequencies (0.205 vs. 0.125) (p<0.004). Striking differences were found between Roma and Hungarian samples in CYP2C19*1 (79.5 vs. 87.4%) and CYP2C19*2 (20.5 vs. 12.6%) alleles, respectively (p<0.001). None of the subjects was found to carry the CYP2C19*3 allele. Frequencies of the intermedier metabolizer phenotype defined by the *1/*2 genotype (0.318 vs. 0.230, p<0.005) and poor metabolizer predicted by the *2/*2 genotype (0.046 vs. 0.011, p<0.005) was significantly higher in Roma than in Hungarians, respectively. Genotype distribution of the Roma population was similar to those of the population of North India, however, a major difference was found in the frequency of the CYP2C19*2 allele, which is likely a result of admixture with European lineages. In conclusion, the frequencies of the CYP2C19 alleles, genotypes and corresponding extensive, intermediate and poor metabolizer phenotypes studied here in the Hungarian population are similar to those of other European Caucasian populations, but display clear differences when compared to the Roma population.
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Affiliation(s)
- Csilla Sipeky
- Department of Medical Genetics, University of Pecs, Szigeti 12, Pecs, 7624, Hungary.
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Hu LM, Dai DP, Hu GX, Yang JF, Xu RA, Yang LP, Qian JC, Ge RS, Cai JP. Genetic polymorphisms and novel allelic variants of CYP2C19 in the Chinese Han population. Pharmacogenomics 2012; 13:1571-81. [PMID: 23148634 DOI: 10.2217/pgs.12.141] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Aim: This study aims to systematically investigate the genetic polymorphisms of the CYP2C19 gene and provide accurate data of the allele distribution pattern in the Chinese Han population. Materials & Methods: We amplified all nine exons of the CYP2C19 gene in 2127 unrelated healthy Chinese Han subjects from two geographical locations (Zhejiang province, n = 1127; Hebei province, n = 1000), using direct sequencing. Results: In total, six previously reported alleles were found in our study, in which two alleles CYP2C19*6 and CYP2C19*18 were reported for the first time in Chinese Han subjects. In addition, 35 novel variants were detected in the present work, which included 11 new named alleles, 12 nonsynonymous mutations and one insert variant. Conclusion: This study provides important data on the pattern of CYP2C19 polymorphisms in Chinese Han subjects, using the largest group of individuals. Furthermore, the study also detects the largest number of novel alleles in one population. These findings are of potential benefit to the development of personalized medicine for the Chinese Han population. Original submitted 25 June 2012; Revision submitted 20 August 2012
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Affiliation(s)
- Li-Ming Hu
- Graduate School, Wenzhou Medical College, University-Town, Wenzhou, Zhejiang 325035, People’s Republic of China
- The Key Laboratory of Geriatrics, Beijing Hospital & Beijing Institute of Geriatrics, Ministry of Health, No. 1, Dahua Road, Dongdan, Beijing 100730, People’s Republic of China
- Department of Pharmacology, Wenzhou Medical College, University-Town, Wenzhou, Zhejiang 325035, People’s Republic of China
| | - Da-Peng Dai
- The Key Laboratory of Geriatrics, Beijing Hospital & Beijing Institute of Geriatrics, Ministry of Health, No. 1, Dahua Road, Dongdan, Beijing 100730, People’s Republic of China
| | - Guo-Xin Hu
- Department of Pharmacology, Wenzhou Medical College, University-Town, Wenzhou, Zhejiang 325035, People’s Republic of China
| | - Jie-Fu Yang
- Department of Cardiology, Beijing Hospital, Ministry of Health, No. 1, Dahua Road, Dongdan, Beijing 100730, People’s Republic of China
| | - Ren-Ai Xu
- Graduate School, Wenzhou Medical College, University-Town, Wenzhou, Zhejiang 325035, People’s Republic of China
- The First Affiliated Hospital of Wenzhou Medical College, Wenzhou, Zhejiang 325035, People’s Republic of China
| | - Li-Ping Yang
- Department of Pharmacy, Beijing Hospital, Ministry of Health, No. 1, Dahua Road, Dongdan, Beijing 100730, People’s Republic of China
| | - Jian-Chang Qian
- Graduate School, Wenzhou Medical College, University-Town, Wenzhou, Zhejiang 325035, People’s Republic of China
- The First Affiliated Hospital of Wenzhou Medical College, Wenzhou, Zhejiang 325035, People’s Republic of China
| | - Ren-Shan Ge
- Department of Pharmacology, Wenzhou Medical College, University-Town, Wenzhou, Zhejiang 325035, People’s Republic of China
- The Second Affiliated Hospital of Wenzhou Medical College, Wenzhou, Zhejiang, 325027, People’s Republic of China
| | - Jian-Ping Cai
- The Key Laboratory of Geriatrics, Beijing Hospital & Beijing Institute of Geriatrics, Ministry of Health, No. 1, Dahua Road, Dongdan, Beijing 100730, People’s Republic of China
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Tucci JD. Pharmacogenetic screening of Indigenous Australians. Med J Aust 2011; 195:386-7. [PMID: 21978343 DOI: 10.5694/mja11.10678] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Accepted: 08/14/2011] [Indexed: 11/17/2022]
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Evolution of detoxifying systems: the role of environment and population history in shaping genetic diversity at human CYP2D6 locus. Pharmacogenet Genomics 2011; 20:485-99. [PMID: 20520586 DOI: 10.1097/fpc.0b013e32833bba25] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The transition from food collection to food production (FP) modified the nature of selective pressures, and several studies illustrate that genetic adaptation to new lifestyle has occurred in humans since the agricultural revolution. Here we test the hypothesis that high levels of genetic variation at CYP2D6, a locus coding for a detoxifying enzyme of the cytochrome P450 complex, reflect this change. METHODS We compared DNA sequences and predicted the levels of enzyme activity across 10 African, Asian and European populations, six of which currently rely on hunting and gathering (HG) while four on food production (FP). RESULTS AND CONCLUSION HG and FP showed similar levels of CYP2D6 diversity, but displayed different substitution patterns at coding DNA sites possibly related to selective differences. Comparison with variation at presumably neutral independent loci confirmed this finding, despite the confounding effects of population history, resulting in higher overall variation in Africans than in Eurasians. The differences between HG and FP populations suggest that new lifestyle and dietary habits acquired in the transition to agriculture affected the variation pattern at CYP2D6, leading to an increase in FP populations of the frequency of alleles that are associated with a slower rate of metabolism. These alleles reached a balanced co-existence with other important and previously selected variants. We suggest that the pronounced substrate-dependent activity of most of these enzymes expanded the spectrum of the metabolic response.
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Tang K, Li X, Xing Q, Li W, Feng G, He L, Qin S. Genetic polymorphism analysis of cytochrome P4502E1 (CYP2E1) in Chinese Han populations from four different geographic areas of Mainland China. Genomics 2010; 95:224-9. [PMID: 20100563 DOI: 10.1016/j.ygeno.2010.01.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2009] [Revised: 11/17/2009] [Accepted: 01/17/2010] [Indexed: 12/26/2022]
Abstract
CYP2E1 is one of a superfamily of enzymes that play a central role in activating and detoxifying many xenobiotics and endogenous compounds thought to be involved in the development of several human diseases. Among other factors, individual susceptibility to developing these pathologies relies on genetic polymorphisms, which are related to ethnic differences, since the frequency of mutant genotypes varies in different populations. The aim of this study was to investigate the genetic basis of CYP2E1 polymorphisms in the populations of four different geographical locations of China. Twenty-two different CYP2E1 polymorphisms, including six novel variants in promoter regions and a novel nonsense mutation, were identified. The frequencies of some polymorphisms and genotypes demonstrated significant differences among the four populations. Linkage disequilibrium analysis and tag SNP selection were performed. Haplotypes were analyzed within the selected tag SNPs. Tag SNP selection and haplotype distributions showed differences across the four populations.
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Affiliation(s)
- Kefu Tang
- Bio-X Center, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Shanghai Jiao Tong University, Shanghai, China
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22
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Zordoky BNM, El-Kadi AOS. Effect of cytochrome P450 polymorphism on arachidonic acid metabolism and their impact on cardiovascular diseases. Pharmacol Ther 2010; 125:446-63. [PMID: 20093140 DOI: 10.1016/j.pharmthera.2009.12.002] [Citation(s) in RCA: 136] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2009] [Accepted: 12/24/2009] [Indexed: 01/27/2023]
Abstract
Cardiovascular diseases (CVDs) remain the leading cause of death in the developed countries. Taking into account the mounting evidence about the role of cytochrome P450 (CYP) enzymes in cardiovascular physiology, CYP polymorphisms can be considered one of the major determinants of individual susceptibility to CVDs. One of the important physiological roles of CYP enzymes is the metabolism of arachidonic acid. CYP epoxygenases such as CYP1A2, CYP2C, and CYP2J2 metabolize arachidonic acid to epoxyeicosatrienoic acids (EETs) which generally possess vasodilating, anti-inflammatory, anti-apoptotic, anti-thrombotic, natriuretic, and cardioprotective effects. Therefore, genetic polymorphisms causing lower activity of these enzymes are generally associated with an increased risk of several CVDs such as hypertension and coronary artery disease. EETs are further metabolized by soluble epoxide hydrolase (sEH) to the less biologically active dihydroxyeicosatrienoic acids (DHETs). Therefore, sEH polymorphism has also been shown to affect arachidonic acid metabolism and to be associated with CVDs. On the other hand, CYP omega-hydroxylases such as CYP4A11 and CYP4F2 metabolize arachidonic acid to 20-hydroxyeicosatetraenoic acid (20-HETE) which has both vasoconstricting and natriuretic effects. Genetic polymorphisms causing lower activity of these enzymes are generally associated with higher risk of hypertension. Nevertheless, some studies have denied the association between polymorphisms in the arachidonic acid pathway and CVDs. Therefore, more research is needed to confirm this association and to better understand the pathophysiologic mechanisms behind it.
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Affiliation(s)
- Beshay N M Zordoky
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada T6G 2N8
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Toscano C, Klein K, Blievernicht J, Schaeffeler E, Saussele T, Raimundo S, Eichelbaum M, Schwab M, Zanger UM. Impaired expression of CYP2D6 in intermediate metabolizers carrying the *41 allele caused by the intronic SNP 2988G>A: evidence for modulation of splicing events. Pharmacogenet Genomics 2009; 16:755-66. [PMID: 17001295 DOI: 10.1097/01.fpc.0000230112.96086.e0] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
We investigated the molecular basis for low expression and activity of CYP2D6 associated with the CYP2D6*41 allele in about 10-15% of Caucasians with intermediate metabolizer phenotype. With respect to two previously described polymorphisms in the promoter (-1584C>G) and in intron 6 (2988G>A; c.985+39G>A), the three most frequent functional alleles have the distinct haplotypes 2D6*1[CG], 2D6*2[GG] and 2D6*41[CA], respectively. Reporter gene analyses in transiently transfected HepG2 and Huh7 hepatoma cells did not indicate changes in transcription rate by these polymorphisms. By reverse-transcription polymerase chain reaction analysis of liver RNA of genotyped patients, however, we discovered that the 2988G>A change was associated with increased levels of a nonfunctional splice variant lacking exon 6. Quantification by denaturing high-performance liquid chromatography revealed up to 7.3-fold increased levels of the splice variant and up to 2.9-fold less functional transcript in carriers of 2D6*41, in good concordance with concomitant changes in immunoquantified CYP2D6 protein. Recombinant expression of the entire genomic sequence coding for 2D6*41, 2D6*2 and 2D6*1 alleles but lacking the upstream region in COS-1 and Huh7 cell lines resulted in two-fold to five-fold reduced levels of CYP2D6 mRNA containing exon 6, apoprotein and enzyme activity of 2D6*41. These experiments establish the causal relationship between the intron 6 single-nucleotide polymorphism 2988G>A and the low expression phenotype associated with allele 2D6*41. These data improve the CYP2D6 genotype-phenotype relationship and they demonstrate that major phenotype changes occurring in large population subgroups can be caused by intronic polymorphisms outside of splice site consensus sequences.
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Affiliation(s)
- Claudia Toscano
- Dr Margarete Fischer-Bosch Institute of Clinical Pharmacology, Stuttgart, Germany
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Frequencies of genotypes and alleles of the functional SNPs in CYP2C19 and CYP2E1 in mainland Chinese Kazakh, Uygur and Han populations. J Hum Genet 2009; 54:372-5. [DOI: 10.1038/jhg.2009.41] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Sabbagh A, Génin E, Darlu P. Selecting Predictive Markers for Pharmacogenetic Traits: Tagging vs. Data-Mining Approaches. Hum Hered 2008; 66:10-8. [DOI: 10.1159/000114161] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2006] [Accepted: 08/16/2007] [Indexed: 11/19/2022] Open
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Genetic polymorphism of CYP2C19 in Maharashtrian population. Eur J Epidemiol 2007; 22:907-15. [DOI: 10.1007/s10654-007-9196-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2006] [Accepted: 10/02/2007] [Indexed: 11/29/2022]
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Hilli J, Rane A, Lundgren S, Bertilsson L, Laine K. Genetic polymorphism of cytochrome P450s and P-glycoprotein in the Finnish population. Fundam Clin Pharmacol 2007; 21:379-86. [PMID: 17635176 DOI: 10.1111/j.1472-8206.2007.00494.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The objective of this study was to investigate the genetic polymorphism of selected cytochrome P450 (CYP) enzymes and ABCB1 (encoding P-glycoprotein) of central importance with regard to the disposition of clinically used drugs in the Finnish population and to compare the results to pre-existing data from Caucasian populations. A random sample of 449 Finns was studied. Single nucleotide polymorphisms (SNPs) were genotyped using blood-derived genomic DNA and 5'-nuclease assays. We found that the allele frequencies of CYP1A2 SNP g.-163C>A, CYP2C8*3, CYP2C9*2, CYP2C9*3 and CYP2C19*2 were similar to those seen in other Caucasian populations. However, the allelic frequency of the variant ABCB1 SNP c.3435C>T allele was lower than previously reported. The frequency of the homozygous CYP3A5*1 expression was significantly higher than expected based on Hardy-Weinberg calculations (observed n = 8 vs. expected n = 3, P = 0.01). Other genotype frequencies corresponded to the expected values. The strong linkage between the CYP2C8*3 and the CYP2C9*2 alleles was confirmed in this study and the number of individuals with the rare haplotype CYP2C8*3*3/CYP2C9*2*2 was higher than expected. We conclude that the frequency of mutated CYP alleles in Finns were in agreement with earlier findings in Caucasian populations, but a lower frequency of the ABCB1 variant allele 3435T corresponding to that reported in Asian populations was found. The higher than expected frequency of the CYP3A5*1*1 genotype and the CYP2C8*3*3/CYP2C9*2*2 haplotype may influence the response to treatment with drugs metabolized by these enzymes.
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Affiliation(s)
- Johanna Hilli
- Department of Pharmacology, Drug Development and Therapeutics, University of Turku, Itäinen Pitkäkatu 4B, 3rd floor, FIN-20520 Turku, Finland.
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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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Alonso-Navarro H, Jiménez-Jiménez FJ, García-Agúndez JA. Papel del polimorfismo genético CYP2C19 en los efectos adversos a fármacos y en el riesgo para diversas enfermedades. Med Clin (Barc) 2006; 126:697-706. [PMID: 16759580 DOI: 10.1157/13088772] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
There are a great number of polymorphic genes in the human genome. Many of them codify enzymes that metabolizes drugs and xenobiotic agents, including carcinogens. Among the better known of them, there are a number of isozymes of the microsomal oxidative system (CYP3A4, CYP2C9, CYP2C19 y CYP2D6). This article reviews the following issues: a) frequency of presentation of the "poor metabolizer" genotype and/or phenotype for substrates of CYP2C19; b) role of CYP2C19 polymorphism on the metabolism of some drugs (mephenytoine and other antiepileptic drugs, proton pump inhibitors, several antidepressants and anxyolitics, the antimalaria aggent proguanyl, and propranolol, among others, use this metabolic pathway), and c) possible role of CYP2C19 polymorphism in the risk for development of neoplasia and other diseases (systemic lupus erythematosus, psoriasis, hip osteonecrosis, Alzheimer's disease, amyotrophic lateral sclerosis, essential tremor).
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Milton AG, Jannes J, Hamilton-Bruce MA, Koblar SA. Activating Mutation of the Renal Epithelial Chloride Channel ClC-Kb Predisposing to Hypertension. Hypertension 2006; 47:e12; author reply e12-3. [PMID: 16446391 DOI: 10.1161/01.hyp.0000203773.85380.1b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Sabbagh A, Darlu P. Data-Mining Methods as Useful Tools for Predicting Individual Drug Response: Application to CYP2D6 Data. Hum Hered 2006; 62:119-34. [PMID: 17057402 DOI: 10.1159/000096416] [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] [Received: 06/08/2006] [Accepted: 08/22/2006] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVES Selecting a maximally informative subset of polymorphisms to predict a clinical outcome, such as drug response, requires appropriate search methods due to the increased dimensionality associated with looking at multiple genotypes. In this study, we investigated the ability of several pattern recognition methods to identify the most informative markers in the CYP2D6 gene for the prediction of CYP2D6 metabolizer status. METHODS Four data-mining tools were explored: decision trees, random forests, artificial neural networks, and the multifactor dimensionality reduction (MDR) method. Marker selection was performed separately in eight population samples of different ethnic origin to evaluate to what extent the most informative markers differ across ethnic groups. RESULTS Our results show that the number of polymorphisms required to predict CYP2D6 metabolic phenotype with a high accuracy can be dramatically reduced owing to the strong haplotype block structure observed at CYP2D6. MDR and neural networks provided nearly identical results and performed the best. CONCLUSION Data-mining methods, such as MDR and neural networks, appear as promising tools to improve the efficiency of genotyping tests in pharmacogenetics with the ultimate goal of pre-screening patients for individual therapy selection with minimum genotyping effort.
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Affiliation(s)
- Audrey Sabbagh
- Unité de Recherche en Génétique Epidémiologique et Structure des Populations Humaines, INSERM U535, Villejuif, France.
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Bravo-Villalta HV, Yamamoto K, Nakamura K, Bayá A, Okada Y, Horiuchi R. Genetic polymorphism of CYP2C9 and CYP2C19 in a Bolivian population: an investigative and comparative study. Eur J Clin Pharmacol 2005; 61:179-84. [PMID: 15776277 DOI: 10.1007/s00228-004-0890-5] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2004] [Accepted: 12/21/2004] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Several reports of CYP2C genetic polymorphism demonstrate its potential clinical role in determining both inter-individual and inter-ethnic differences in drug efficacy. We estimated the distribution of CYP2C9 and CYP2C19 common variants in the Bolivian population (a South American population), and compared these data with those from Asian, African, Caucasian and Oceanian populations. METHODS Genomic DNA was obtained from 778 unrelated healthy volunteers from Bolivia. The genotypic status of CYP2C9 and CYP2C19 was determined by means of polymerase chain reaction-restriction fragment length polymorphism. RESULTS Allelic and genotypic frequencies of CYP2C9 and CYP2C19 were determined for the Bolivian population, and comparison of the data with other ethnic groups revealed a lower CYP2C9*2 frequency (4.8%) than in Caucasians, but a higher frequency than in Asians; frequencies of CYP2C9*3 (3.0%) and CYP2C9 (0.4%) poor metabolizers (PMs) were similar to those seen in Asian populations. Frequencies of CYP2C19*2 (7.8%), CYP2C19*3 (0.1%), and CYP2C19 PMs (1.0%) in the Bolivian population were for the most part lower than in Caucasian, Asian, Oceanian and African populations. CONCLUSION This is the first study to investigate a South American population for genetic polymorphism in the CYP2C subfamily. The Bolivian population differs from most other ethnic groups in the incidence of CYP2C9 and CYP2C19 common variants that might be influenced by its admixture characteristics.
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Affiliation(s)
- Heydy V Bravo-Villalta
- Department of Clinical Pharmacology, Graduate School of Medicine, Gunma University, 3-39-22 Showa-machi, Maebashi, 371-8511, Japan
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Zanger UM, Raimundo S, Eichelbaum M. Cytochrome P450 2D6: overview and update on pharmacology, genetics, biochemistry. Naunyn Schmiedebergs Arch Pharmacol 2003; 369:23-37. [PMID: 14618296 DOI: 10.1007/s00210-003-0832-2] [Citation(s) in RCA: 553] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2003] [Accepted: 09/18/2003] [Indexed: 01/21/2023]
Abstract
Of about one dozen human P450 s that catalyze biotransformations of xenobiotics, CYP2D6 is one of the more important ones based on the number of its drug substrates. It shows a very high degree of interindividual variability, which is primarily due to the extensive genetic polymorphism that influences expression and function. This so-called debrisoquine/sparteine oxidation polymorphism has been extensively studied in many different populations and over 80 alleles and allele variants have been described. CYP2D6 protein and enzymatic activity is completely absent in less than 1% of Asian people and in up to 10% of Caucasians with two null alleles, which do not encode a functional P450 protein product. The resulting "poor metabolizer" (PM) phenotype is characterized by the inability to use CYP2D6-dependent metabolic pathways for drug elimination, which affect up to 20% of all clinically used drugs. The consequences are increased risk of adverse drug reactions or lack of therapeutic response. Today, genetic testing predicts the PM phenotype with over 99% certainty. At the other extreme, the "Ultrarapid Metabolizer" (UM) phenotype can be caused by alleles carrying multiple gene copies. "Intermediate Metabolizers" (IM) are severely deficient in their metabolism capacity compared to normal "Extensive Metabolizers" (EM), but in contrast to PMs they express a low amount of residual activity due to the presence of at least one partially deficient allele. Whereas the intricate genetics of the CYP2D6 polymorphism is becoming apparent at ever greater detail, applications in clinical practice are still rare. More clinical studies are needed to show where patients benefit from drug dose adjustment based on their genotype. Computational approaches are used to predict and rationalize substrate specificity and enzymatic properties of CYP2D6. Pharmacophore modeling of ligands and protein homology modeling are two complementary approaches that have been applied with some success. CYP2D6 is not only expressed in liver but also in the gut and in brain neurons, where endogenous substrates with high-turnover have been found. Whether and how brain functions may be influenced by polymorphic expression are interesting questions for the future.
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Affiliation(s)
- Ulrich M Zanger
- Dr. Margarete Fischer-Bosch Institute of Clinical Pharmacology, Auerbachstrasse 112, 70376, Stuttgart, Germany.
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Yusuf I, Djojosubroto MW, Ikawati R, Lum K, Kaneko A, Marzuki S. Ethnic and geographical distributions of CYP2C19 alleles in the populations of Southeast Asia. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2003; 531:37-46. [PMID: 12916779 DOI: 10.1007/978-1-4615-0059-9_3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Affiliation(s)
- Irawan Yusuf
- Eijkman Institute for Molecular Biology, Jakarta, Indonesia.
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Nicholson JK, Wilson ID. Opinion: understanding 'global' systems biology: metabonomics and the continuum of metabolism. Nat Rev Drug Discov 2003; 2:668-76. [PMID: 12904817 DOI: 10.1038/nrd1157] [Citation(s) in RCA: 760] [Impact Index Per Article: 36.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Jeremy K Nicholson
- Biological Chemistry, Biomedical Sciences Division, Faculty of Medicine, Imperial College London, Sir Alexander Fleming Building, South Kensington, London, SW7 2AZ, UK.
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Abstract
Many administered drugs are first activated by phase I drug-metabolizing enzymes, such as cytochrome P450 (CYP), and then conjugated with ligands such as UDPGA, PAPS, and glutathione by phase II drug-metabolizing enzymes, and finally excreted by transporters. There are some defective activity mutants due to CYP polymorphisms. In these cases, drugs are not metabolized [poor metabolizer (PM)], the high drug levels in blood are maintained, and toxic effects appear in the patients. To clarify the ratio of PMs, in the general population, it is necessary to estimate the drug level to not only prevent toxic reactions, but also to provide more efficient drug therapies, according to their polymorphic information about CYPs. In Caucasians and Asians, PM and allele frequency levels of CYPs (CYP2A6, CYP2C9, CYP2C19, CYP2D6, and CYP3A4) are summarized from previous findings. In Caucasians, high PM ratios (7%) of CYP2D6 deriving from the high frequency of CYP2D6*4 and CYP2D6*5, and 2% CYP2C19 from CYP2C19*2, were found. Meanwhile, in Asians, high PM ratios (19%) of CYP2C19 from high frequencies of CYP2C19*2 and CYP2C19*3, and 2% to 4% CYP2A6 from CYP2A6*4, were found. In both populations, the PM frequencies of the CYP3A4 of major drug-metabolizing CYP and CYP2C9 were low.
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Affiliation(s)
- Takaharu Mizutani
- Department of Drug Metabolism and Disposition, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan.
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Schaefer BM, Caracciolo V, Frishman WH, Charney P. Gender, ethnicity and genetics in cardiovascular disease: part 1: Basic principles. HEART DISEASE (HAGERSTOWN, MD.) 2003; 5:129-43. [PMID: 12713680 DOI: 10.1097/01.hdx.0000061694.62343.01] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Prior to 1993, most drug efficacy and safety trials were conducted in white males, although gender and racial differences in pharmacodynamics and pharmacokinetics have been documented since the early 1900s. Over the last 2 decades, supported by the FDA and legislation, attempts to include more women and minorities in clinical drug trials have been made, with limited success. Yet, there are important differences in pathophysiology and pharmacogenetics, as well as pharmacotherapeutic effectiveness. This is the first of 2 articles that review the basic scientific principles of such differences. In particular, genetic polymorphisms of cardiovascular candidate genes and drug metabolism are described. The pharmacodynamic and pharmacokinetic variations among genders and ethnicities are summarized.
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Desta Z, Zhao X, Shin JG, Flockhart DA. Clinical significance of the cytochrome P450 2C19 genetic polymorphism. Clin Pharmacokinet 2002; 41:913-58. [PMID: 12222994 DOI: 10.2165/00003088-200241120-00002] [Citation(s) in RCA: 584] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Cytochrome P450 2C19 (CYP2C19) is the main (or partial) cause for large differences in the pharmacokinetics of a number of clinically important drugs. On the basis of their ability to metabolise (S)-mephenytoin or other CYP2C19 substrates, individuals can be classified as extensive metabolisers (EMs) or poor metabolisers (PMs). Eight variant alleles (CYP2C19*2 to CYP2C19*8) that predict PMs have been identified. The distribution of EM and PM genotypes and phenotypes shows wide interethnic differences. Nongenetic factors such as enzyme inhibition and induction, old age and liver cirrhosis can also modulate CYP2C19 activity. In EMs, approximately 80% of doses of the proton pump inhibitors (PPIs) omeprazole, lansoprazole and pantoprazole seem to be cleared by CYP2C19, whereas CYP3A is more important in PMs. Five-fold higher exposure to these drugs is observed in PMs than in EMs of CYP2C19, and further increases occur during inhibition of CYP3A-catalysed alternative metabolic pathways in PMs. As a result, PMs of CYP2C19 experience more effective acid suppression and better healing of duodenal and gastric ulcers during treatment with omeprazole and lansoprazole compared with EMs. The pharmacoeconomic value of CYP2C19 genotyping remains unclear. Our calculations suggest that genotyping for CYP2C19 could save approximately 5000 US dollars for every 100 Asians tested, but none for Caucasian patients. Nevertheless, genotyping for the common alleles of CYP2C19 before initiating PPIs for the treatment of reflux disease and H. pylori infection is a cost effective tool to determine appropriate duration of treatment and dosage regimens. Altered CYP2C19 activity does not seem to increase the risk for adverse drug reactions/interactions of PPIs. Phenytoin plasma concentrations and toxicity have been shown to increase in patients taking inhibitors of CYP2C19 or who have variant alleles and, because of its narrow therapeutic range, genotyping of CYP2C19 in addition to CYP2C9 may be needed to optimise the dosage of phenytoin. Increased risk of toxicity of tricyclic antidepressants is likely in patients whose CYP2C19 and/or CYP2D6 activities are diminished. CYP2C19 is a major enzyme in proguanil activation to cycloguanil, but there are no clinical data that suggest that PMs of CYP2C19 are at a greater risk for failure of malaria prophylaxis or treatment. Diazepam clearance is clearly diminished in PMs or when inhibitors of CYP2C19 are coprescribed, but the clinical consequences are generally minimal. Finally, many studies have attempted to identify relationships between CYP2C19 genotype and phenotype and susceptibility to xenobiotic-induced disease, but none of these are compelling.
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Affiliation(s)
- Zeruesenay Desta
- Division of Clinical Pharmacology, Indiana University School of Medicine, Wishard Hospital, Indianapolis 46202, USA
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Gaspar PA, Hutz MH, Salzano FM, Hill K, Hurtado AM, Petzl-Erler ML, Tsuneto LT, Weimer TA. Polymorphisms of CYP1a1, CYP2e1, GSTM1, GSTT1, and TP53 genes in Amerindians. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2002; 119:249-56. [PMID: 12365037 DOI: 10.1002/ajpa.10128] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Polymorphisms at the TP53, cytochrome P-450 (CYP), and glutathione S-transferase (GST) genes are related to cancer susceptibility and present high diversity in allele frequencies among ethnic groups. This study concerns the CYP2E1, GSTM1, and GSTT1 polymorphisms in seven Amerindian populations (Xavante, Guarani, Aché, Wai Wai, Zoró, Surui, and Gavião). Polymorphic sites at CYP1A1 and TP53 were also studied in the Aché and Guarani tribes and compared with previous results about these systems already obtained in the other populations. The CYP2E1*5B haplotype showed, respectively, the highest and the lowest frequencies already observed in human groups. High frequencies of CYP1A1*2A and CYP1A1*2C alleles and mostly low values of GSTM1*0/*0 and GSTT1*0/*0 genotypes were observed. These data may be interpreted as being due to genetic drift or selection for these high-frequency CYP1A1 alleles and against GST null genotypes during America's colonization. Intrapopulation diversity varied from 0.19 (Guarani) to 0.38 (Surui), and 90% of the total diversity was due to the variability within populations. The relationships between these Amerindians and with other ethnic groups were evaluated based on D(A) distances and the neighbor-joining method. Low correlation was observed between genetic relationships and geographic distances or linguistic groups. In the TP53 comparison with other ethnic groups, Amerindians clustered together and then joined Chinese populations. The cluster analysis seems to indicate that the Aché tribe might descend from a Gê group that could have first colonized that Paraguayan region, but had also assimilated some amount of the Guarani gene pool, maybe through intertribal admixture.
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Affiliation(s)
- Pedro A Gaspar
- Departamento de Genética, Universidade Federal do Rio Grande do Sul, 91501-970 Porto Alegre, RS, Brazil
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Chang AB, Boyce NC, Masters IB, Torzillo PJ, Masel JP. Bronchoscopic findings in children with non-cystic fibrosis chronic suppurative lung disease. Thorax 2002; 57:935-8. [PMID: 12403874 PMCID: PMC1746234 DOI: 10.1136/thorax.57.11.935] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND Published data on the frequency and types of flexible bronchoscopic airway appearances in children with non-cystic fibrosis bronchiectasis and chronic suppurative lung disease are unavailable. The aims of this study were to describe airway appearances and frequency of airway abnormalities and to relate these airway abnormalities to chest high resolution computed tomography (cHRCT) findings in a cohort of children with non-cystic fibrosis chronic suppurative lung disease (CSLD). METHODS Indigenous children with non-cystic fibrosis CSLD (>4 months moist and/or productive cough) were prospectively identified and collected over a 2.5 year period at two paediatric centres. Their medical charts and bronchoscopic notes were retrospectively reviewed. RESULTS In all but one child the aetiology of the bronchiectasis was presumed to be following a respiratory infection. Thirty three of the 65 children with CSLD underwent bronchoscopy and five major types of airway findings were identified (mucosal abnormality/inflammation only, bronchomalacia, obliterative-like lesion, malacia/obliterative-like combination, and no macroscopic abnormality). The obliterative-like lesion, previously undescribed, was present in 16.7% of bronchiectatic lobes. Structural airway lesions (bronchomalacia and/or obliterative-like lesion) were present in 39.7% of children. These lesions, when present, corresponded to the site of abnormality on the cHRCT scan. CONCLUSIONS Structural airway abnormality is commonly found in children with post-infectious bronchiectasis and a new bronchoscopic finding has been described. Airway abnormalities, when present, related to the same lobe abnormality on the cHRCT scan. How these airway abnormalities relate to aetiology, management strategy, and prognosis is unknown.
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Affiliation(s)
- A B Chang
- Department of Respiratory Medicine, Royal Children's Hospital, Herston, Queensland, Australia.
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McCarthy LC, Davies KJ, Campbell DA. Pharmacogenetics in diverse ethnic populations--implications for drug discovery and development. Pharmacogenomics 2002; 3:493-506. [PMID: 12164773 DOI: 10.1517/14622416.3.4.493] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
It is widely acknowledged that the vast quantities of data now publicly available as a result of the human genome initiative have the potential to revolutionize the pharmaceutical industry. More tangibly to the drug development business, the dawn of the pharmacogenetics era has the potential to impact not only the discovery of new medicines but also the safety and efficacy of pharmaceutical agents. Coincident with these scientific advances is the emergence of new markets for pharmaceutical agents. Japan, which represents the world's second biggest market, is a good example. With the ICH E5 agreement in 1998 and a rapid change in the drug registration process in Japan, there are increasing opportunities to improve access to more medicines in all parts of the world. However, it is increasingly clear that significant genetic variation still exists between populations, with a host of data on interethnic variation in drug metabolizing enzyme and drug transporter activity. Evidence suggesting that this genetic variation may play an important role in defining some of the interethnic variation in drug response to currently marketed compounds is reviewed here, and future possibilities of using such information to better streamline the drug development process are discussed.
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Affiliation(s)
- Linda C McCarthy
- Medicines Research Centre, Gunnels Wood Road, Stevenage, Herts, SG1 2NY, UK
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Hamdy SI, Hiratsuka M, Narahara K, El-Enany M, Moursi N, Ahmed MSE, Mizugaki M. Allele and genotype frequencies of polymorphic cytochromes P450 (CYP2C9, CYP2C19, CYP2E1) and dihydropyrimidine dehydrogenase (DPYD) in the Egyptian population. Br J Clin Pharmacol 2002; 53:596-603. [PMID: 12047484 PMCID: PMC1874334 DOI: 10.1046/j.1365-2125.2002.01604.x] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2001] [Accepted: 01/14/2002] [Indexed: 11/20/2022] Open
Abstract
AIMS The goal of this study was to determine the frequencies of important allelic variants of CYP2C9, CYP2C19, CYP2E1 and DPYD in the Egyptian population and compare them with the frequencies in other ethnic populations. METHODS Genotyping of CYP2C9 (*2 and *3), CYP2C19 (*2 and *3), c2 variant of CYP2E1 and DPYD alleles (*2 A-*6 ) was carried out in a total of 247 unrelated Egyptian subjects. An allele-specific fluorogenic 5' nuclease chain reaction assay was applied for detection of CYP2C9 and CYP2C19 variants. Other variants of the CYP2E1 and DPYD genes were determined using polymerase chain reaction (PCR)-restriction fragment length polymorphism and allele-specific PCR based assays. RESULTS CYP2C9 allele frequencies in 247 Egyptian subjects were 0.820 for CYP2C9*1, 0.120 for CYP2C9*2 and 0.060 for CYP2C9*3. For CYP2C19, the frequencies of the wild type (CYP2C19*1) and the nonfunctional (*2 and *3) alleles were 0.888, 0.110 and 0.002, respectively. CYP2C19*3, which is considered an Asian mutation, was detected in one subject (0.40%) who was heterozygous (*1/*3). Two subjects (0.80%) were homozygous for *2/*2, while no compound heterozygotes (*2/*3) or homozygotes for *3 were detected. For CYP2E1, only four subjects (1.70%) had the rare c2 variant, expressed heterozygously, giving an allele frequency of 0.009. Five variants of DPYD were analysed, with no splice sites (*2 A) or DeltaC1897 (*3) found in this population. The frequencies of other variants were 0.028, 0.115 and 0.090 for *4, *5 and *6, respectively. CONCLUSIONS Comparing our data with that obtained in several Caucasian, African-American and Asian populations, we found that Egyptians resemble Caucasians with regard to allelic frequencies of the tested variants of CYP2C9, CYP2C19, CYP2E1 and DPYD. Our results may help in better understanding the molecular basis underlying ethnic differences in drug response, and contribute to improved individualization of drug therapy in the Egyptian population.
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Affiliation(s)
- Samar Ismail Hamdy
- Department of Pharmaceutical Sciences, Tohoku University HospitalJapan
- Faculty of Pharmacy, Cairo UniversityEgypt
| | | | - Kaori Narahara
- Department of Pharmaceutical Sciences, Tohoku University HospitalJapan
| | | | | | | | - Michinao Mizugaki
- Department of Pharmaceutical Sciences, Tohoku University HospitalJapan
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