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Rodrigues-Soares F, Kehdy FSG, Sampaio-Coelho J, Andrade PXC, Céspedes-Garro C, Zolini C, Aquino MM, Barreto ML, Horta BL, Lima-Costa MF, Pereira AC, LLerena A, Tarazona-Santos E. Genetic structure of pharmacogenetic biomarkers in Brazil inferred from a systematic review and population-based cohorts: a RIBEF/EPIGEN-Brazil initiative. THE PHARMACOGENOMICS JOURNAL 2018; 18:749-759. [PMID: 29713005 DOI: 10.1038/s41397-018-0015-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 11/07/2017] [Accepted: 02/09/2018] [Indexed: 12/13/2022]
Abstract
We present allele frequencies involving 39 pharmacogenetic biomarkers studied in Brazil, and their distribution on self-reported race/color categories that: (1) involve a mix of perceptions about ancestry, morphological traits, and cultural/identity issues, being social constructs pervasively used in Brazilian society and medical studies; (2) are associated with disparities in access to health services, as well as in their representation in genetic studies, and (3), as we report here, explain a larger portion of the variance of pharmaco-allele frequencies than geography. We integrated a systematic review of studies on healthy volunteers (years 1968-2017) and the analysis of allele frequencies on three population-based cohorts from northeast, southeast, and south, the most populated regions of Brazil. Cross-validation of results from these both approaches suggest that, despite methodological heterogeneity of the 120 studies conducted on 51,747 healthy volunteers, allele frequencies estimates from systematic review are reliable. We report differences in allele frequencies between color categories that persist despite the homogenizing effect of >500 years of admixture. Among clinically relevant variants: CYP2C9*2 (null), CYP3A5*3 (defective), SLCO1B1-rs4149056(C), and VKORC1-rs9923231(A) are more frequent in Whites than in Blacks. Brazilian Native Americans show lower frequencies of CYP2C9*2, CYP2C19*17 (increased activity), and higher of SLCO1B1-rs4149056(C) than other Brazilian populations. We present the most current and informative database of pharmaco-allele frequencies in Brazilian healthy volunteers.
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Affiliation(s)
- Fernanda Rodrigues-Soares
- Departamento de Biologia Geral, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.,Gerência de Malária, Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, AM, Brazil
| | - Fernanda S G Kehdy
- Departamento de Biologia Geral, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.,Laboratório de Hanseníase, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brazil
| | - Julia Sampaio-Coelho
- Departamento de Biologia Geral, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Poliana X C Andrade
- Departamento de Biologia Geral, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Carolina Céspedes-Garro
- Education and Research Department, Genetics Section, School of Biology, University of Costa Rica, San José, Costa Rica
| | - Camila Zolini
- Departamento de Biologia Geral, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.,Beagle, Belo Horizonte, MG, Brazil
| | - Marla M Aquino
- Departamento de Biologia Geral, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Mauricio L Barreto
- Instituto de Saúde Coletiva, Universidade Federal da Bahia, Salvador, BA, 40110-040, Brazil.,Center for Data and Knowledge Integration for Health, Institute Gonçalo Muniz, Fundação Oswaldo Cruz, Salvador, BA, Brazil
| | - Bernardo L Horta
- Programa de Pós-Graduação em Epidemiologia, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | | | | | - Adrián LLerena
- CICAB Clinical Research Centre, Extremadura University Hospital and Medical School, Badajoz, Extremadura, Spain.,Centro de Investigación Biomédica en Red: Salud Mental, CIBERSAM, Madrid, Spain
| | - Eduardo Tarazona-Santos
- Departamento de Biologia Geral, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
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Tamashiro EY, Felipe CR, Genvigir FDV, Rodrigues AC, Campos AB, Hirata RDC, Tedesco-Silva H, Medina-Pestana JO. Influence of CYP3A4 and CYP3A5 polymorphisms on tacrolimus and sirolimus exposure in stable kidney transplant recipients. Drug Metab Pers Ther 2017; 32:89-95. [PMID: 28593920 DOI: 10.1515/dmpt-2016-0036] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 03/07/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND Polymorphisms in genes encoding for drug-metabolizing enzymes and drug transporters are among multiple factors that modulate the pharmacokinetic variability of tacrolimus (TAC) and sirolimus (SRL). This study aimed to evaluate the influence of single nucleotide polymorphisms (SNPs) on TAC and SRL dose-adjusted concentrations (C0/D) in stable kidney transplant recipients. METHODS This is an exploratory and prospective study, which includes 46 stable kidney transplant recipients. These patients were monitored from the 3rd to the 24th month after transplantation. The SRL group consisted of 25 patients receiving TAC, prednisone (PRED), and mycophenolate sodium (MPS), which were converted from TAC to SRL at 3rd month after transplantation. The TAC group consisted of 21 patients who underwent treatment with TAC, PRED, and MPS. Both groups were genotyped for CYP3A4 rs2242480 (g.20230G>A), CYP3A5 rs15524 (g.31611C>T), CYP2C8 rs10509681 (c.1196A>G) and ABCB1 rs1045642 (c.3435C>T), rs1128503 (c.1236C>T), and rs2032582 (c.2677G>T/A) polymorphisms. RESULTS In the TAC group, CYP3A4 rs2242480 A allele carriers were associated with lower TAC C0/D. For CYP3A5 rs15524 SNP, C0/D was higher among patients carrying TT genotype when compared with CT and CC genotype carriers in the SRL and, more consistently, in the TAC groups. For ABCB1 rs1045642 SNP, TT genotype was associated with reduced SRL C0/D, but only at month 15. CONCLUSIONS CYP3A4 rs2242480 and CYP3A5 rs15524 SNPs resulted in significant changes in SRL and TAC C0/D at different times after transplantation.
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Cusinato DAC, Lacchini R, Romao EA, Moysés-Neto M, Coelho EB. Relationship of CYP3A5 genotype and ABCB1 diplotype to tacrolimus disposition in Brazilian kidney transplant patients. Br J Clin Pharmacol 2015; 78:364-72. [PMID: 24528196 DOI: 10.1111/bcp.12345] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Accepted: 01/24/2014] [Indexed: 01/19/2023] Open
Abstract
AIMS Tacrolimus (TAC) is one of the most successful immunosuppressive drugs in transplantation. Its pharmacokinetics (PK) and pharmacogenetics (PG) have been extensively studied, with many studies showing the influence of CYP3A5 on TAC metabolism and bioavailability. However, data concerning the functional significance of ABCB1 polymorphisms are uncertain due to inconsistent results. We evaluated the association between ABCB1 diplotypes, CYP3A5 polymorphisms and TAC disposition in a cohort of Brazilian transplant recipients. METHODS Individuals were genotyped for the CYP3A5*3 allele and ABCB1 polymorphisms (2677G>A/T, 1236C>T, 3435C/T) using a TaqMan® PCR technique. Diplotypes were analyzed for correlation with the TAC dose-normalized ratio (Co : dose). RESULTS We genotyped 108 Brazilian kidney recipients for CYP3A5 (11% CYP3A5*1/*1; 31% CYP3A5*1/*3 and 58% CYP3A5*3/*3) and ABCB1 haplotypes (42% CGC/CGC; 41% GCG/TTT and 17% TTT/TTT). Homozygous subjects for the CYP3A5*3 allele or carriers of the ABCB1 TTT/TTT diplotype showed a higher Co : dose ratio compared with wild type subjects [median (interquartile range) 130.2 (97.5-175.4) vs. 71.3 (45.6-109.0), P < 0.0001 and 151.8 (112.1-205.6) vs. 109.6 (58.1-132.9), P = 0.01, respectively]. When stratified for the CYP3A5*3 group, ABCB1 TTT/TTT individuals showed a higher Co : dose ratio compared with non-TTT/TTT individuals [167.8 (130.4-218.0) vs. 119.4 (100.2-166.3), P = 0.04]. Multivariate linear regression analysis showed that the effects of CYP3A5 polymorphisms and ABCB1 diplotypes remained significant after correction for confounding factors. CONCLUSIONS CYP3A5 is the major enzyme responsible for the marked interindividual variability in TAC PK, but it cannot be considered alone when predicting dose adjustment because ABCB1 diplotypes also affect TAC disposition, showing independent and additive effects on the TAC dose-normalized concentration.
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Affiliation(s)
- Diego Alberto C Cusinato
- Department of Pharmacology, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Av. Bandeirantes, 3900, 14049-900, Ribeirão Preto, São Paulo, Brazil
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CHRNA3 and CYP3A5*3 genotype, lung function and chronic obstructive pulmonary disease in the general population. Pharmacogenet Genomics 2015; 24:220-9. [PMID: 24535486 DOI: 10.1097/fpc.0000000000000038] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
OBJECTIVE Genetic variations are most likely an additional risk factor besides tobacco smoking per se for the risk of chronic obstructive pulmonary disease (COPD). In this study, we compared genetic variants influencing the effect of smoking on COPD, that is, the effect of the well-known splicing defect polymorphism, CYP3A5*3 (rs776746), identified before genome-wide association studies, with the genome-wide association studies identified CHRNA3 (rs1051730) polymorphism on the risk of decreased lung function and COPD. MATERIALS AND METHODS In all, 10 605 participants from the general population were genotyped. Information on spirometry, hospital admissions and smoking behaviour was recorded. Endpoints were lung function and COPD. RESULTS For CHRNA3, the percentage of forced expiratory volume in 1 s (FEV1%) predicted was 89.3, 90.6 and 92.4% in homozygous, heterozygous and noncarrier ever-smokers (P-trend<0.001). The corresponding values for forced vital capacity percentage (FVC%) predicted were 94.5, 95.2 and 96.7% (P-trend<0.001), and for FEV1/FVC ratio, the values were 0.753, 0.760 and 0.764 (P-trend=0.008). The odds ratio for COPD in homozygous versus noncarrier ever-smokers was 1.5 [95% confidence interval (CI) 1.3-1.9] for COPD hospitalization, 1.3 (95% CI 1.1-1.6) for COPD defined as FEV1/FVC less than lower limit of normal, 1.3 (95% CI 1.0-1.5) for the Global Initiative for Chronic Obstructive Lung Disease category 1-4 (GOLD 1-4), 1.2 (95% CI 1.0-1.5) for GOLD 2-4 and 1.5 (95% CI 1.1-2.2) for GOLD 3-4. This association could not be found in never-smokers. No association was found for CYP3A5*3. CONCLUSION The CHRNA3 genotype is associated with decreased lung function and risk of COPD among ever-smokers, whereas this was not the case for CYP3A5*3.
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Mustafina OE, Tuktarova IA, Karimov DD, Somova RS, Nasibullin TR. CYP2D6, CYP3A5, and CYP3A4 gene polymorphisms in Russian, Tatar, and Bashkir populations. RUSS J GENET+ 2015. [DOI: 10.1134/s1022795415010081] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Brewster PWH, Melrose RJ, Marquine MJ, Johnson JK, Napoles A, MacKay-Brandt A, Farias S, Reed B, Mungas D. Life experience and demographic influences on cognitive function in older adults. Neuropsychology 2014; 28:846-58. [PMID: 24933483 PMCID: PMC4227962 DOI: 10.1037/neu0000098] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
OBJECTIVE We examined the influence of a broad spectrum of life experiences on longitudinal cognitive trajectories in a demographically diverse sample of older adults. METHOD Participants were 333 educationally, ethnically, and cognitively diverse older adults enrolled in a longitudinal aging study. Mixed-effects regression was used to measure baseline status in episodic memory, executive functioning, and semantic memory and change in a global cognition factor defined by change in these 3 domain-specific measures. We examined effects of life experience variables (literacy, childhood socioeconomic status, morphometric measures of physical development, life course physical and recreational activity) on longitudinal cognitive trajectories, covarying for age, apolipoprotein E (APOE) genotype and demographics (education, ethnicity, language). RESULTS Non-Latino Whites had higher baseline cognition, but life experience variables attenuated ethnic differences in cognitive scores. Age, literacy, childhood socioeconomic status, and physical activity significantly influenced baseline cognition. Age, APOE ε4, and decline in intellectually and socially stimulating recreational activity from mid to late life were independently associated with increased late life cognitive decline. Higher literacy and late life recreational activity were associated with less decline. Literacy had similar effects for English and Spanish readers/speakers. Bilingual English and Spanish speakers did not differ from English Speakers in cognitive performance. CONCLUSIONS Life experience variables, especially literacy level, were strongly related to baseline cognition and substantially attenuated effects of race/ethnicity and education. Cognitive change was best explained by age, APOE ε4, literacy, and current recreational activities. Literacy had robust associations with baseline cognition and cognitive change in both English and Spanish speakers.
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Affiliation(s)
| | - Rebecca J Melrose
- Brain, Behavior, and Aging Research Center, VA Greater Los Angeles Healthcare System
| | | | | | - Anna Napoles
- Center for Aging in Diverse Communities, Department of Medicine, University of California
| | - Anna MacKay-Brandt
- Department of Outpatient Research, Nathan Kline Institute for Psychiatric Research
| | | | - Bruce Reed
- Department of Neurology, School of Medicine
| | - Dan Mungas
- Department of Neurology, School of Medicine
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Friedrich DC, Genro JP, Sortica VA, Suarez-Kurtz G, de Moraes ME, Pena SDJ, dos Santos ÂKR, Romano-Silva MA, Hutz MH. Distribution of CYP2D6 alleles and phenotypes in the Brazilian population. PLoS One 2014; 9:e110691. [PMID: 25329392 PMCID: PMC4203818 DOI: 10.1371/journal.pone.0110691] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 09/15/2014] [Indexed: 12/24/2022] Open
Abstract
The CYP2D6 enzyme is one of the most important members of the cytochrome P450 superfamily. This enzyme metabolizes approximately 25% of currently prescribed medications. The CYP2D6 gene presents a high allele heterogeneity that determines great inter-individual variation. The aim of this study was to evaluate the variability of CYP2D6 alleles, genotypes and predicted phenotypes in Brazilians. Eleven single nucleotide polymorphisms and CYP2D6 duplications/multiplications were genotyped by TaqMan assays in 1020 individuals from North, Northeast, South, and Southeast Brazil. Eighteen CYP2D6 alleles were identified in the Brazilian population. The CYP2D6*1 and CYP2D6*2 alleles were the most frequent and widely distributed in different geographical regions of Brazil. The highest number of CYPD6 alleles observed was six and the frequency of individuals with more than two copies ranged from 6.3% (in Southern Brazil) to 10.2% (Northern Brazil). The analysis of molecular variance showed that CYP2D6 is homogeneously distributed across different Brazilian regions and most of the differences can be attributed to inter-individual differences. The most frequent predicted metabolic status was EM (83.5%). Overall 2.5% and 3.7% of Brazilians were PMs and UMs respectively. Genomic ancestry proportions differ only in the prevalence of intermediate metabolizers. The IM predicted phenotype is associated with a higher proportion of African ancestry and a lower proportion of European ancestry in Brazilians. PM and UM classes did not vary among regions and/or ancestry proportions therefore unique CYP2D6 testing guidelines for Brazilians are possible and could potentially avoid ineffective or adverse events outcomes due to drug prescriptions.
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Affiliation(s)
- Deise C. Friedrich
- Departamento de Genética, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Júlia P. Genro
- Departamento de Genética, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Vinicius A. Sortica
- Departamento de Genética, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Guilherme Suarez-Kurtz
- Programa de Farmacologia, Instituto Nacional de Cancer, Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Sergio D. J. Pena
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | | | - Marco A. Romano-Silva
- Instituto Nacional de Ciência e Tecnologia de Medicina Molecular, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Mara H. Hutz
- Departamento de Genética, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
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Suarez-Kurtz G, Paula DP, Struchiner CJ. Pharmacogenomic implications of population admixture: Brazil as a model case. Pharmacogenomics 2014; 15:209-19. [DOI: 10.2217/pgs.13.238] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The heterogeneous Brazilian population, with European, African and Amerindian ancestral roots is a model case for exploring the impact of population admixture on the frequency distribution of polymorphisms in pharmacogenes, and the design and interpretation of pharmacogenomics trials. Examples drawn from studies carried out by researchers of the Brazilian pharmacogenomics network, support the following conclusions: the distribution of polymorphisms varies across geographical regions and self-reported ‘race/color’ categories, and is best modeled as continuous functions of individual proportions of European and African ancestry; the differential frequency of polymorphisms impacts the calculations of sample sizes required for adequate statistical power in clinical trials performed in different segments of the Brazilian population; and extrapolation of pharmacogenomics data from well-defined ethnic groups to Brazilians is plagued with uncertainty. Data for warfarin and tacrolimus are reviewed to highlight the advantages and challenges of performing pharmacogenomic trials in Brazilians.
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Affiliation(s)
- Guilherme Suarez-Kurtz
- Programa de Farmacologia, Instituto Nacional do Câncer, Rio de Janeiro, RJ, 20231-050, Brazil
| | - Daniela Polessa Paula
- Departamento de Matemática, Instituto de Ciências Exatas, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ 23890-000, Brazil
| | - Claudio J Struchiner
- Programa de Computação Científica, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, 21040-360, Brazil
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Characterization of CYP1A2, CYP2C19, CYP3A4 and CYP3A5 polymorphisms in South Brazilians. Mol Biol Rep 2014; 41:1453-60. [DOI: 10.1007/s11033-013-2990-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2012] [Accepted: 12/24/2013] [Indexed: 12/11/2022]
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Suarez-Kurtz G. Ethnic differences in drug therapy: a pharmacogenomics perspective. Expert Rev Clin Pharmacol 2014; 1:337-9. [DOI: 10.1586/17512433.1.3.337] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Suarez-Kurtz G, Vargens DD, Santoro AB, Hutz MH, de Moraes ME, Pena SDJ, Ribeiro-dos-Santos Â, Romano-Silva MA, Struchiner CJ. Global pharmacogenomics: distribution of CYP3A5 polymorphisms and phenotypes in the Brazilian population. PLoS One 2014; 9:e83472. [PMID: 24427273 PMCID: PMC3888384 DOI: 10.1371/journal.pone.0083472] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Accepted: 11/04/2013] [Indexed: 11/19/2022] Open
Abstract
The influence of self-reported "race/color", geographical origin and genetic ancestry on the distribution of three functional CYP3A5 polymorphisms, their imputed haplotypes and inferred phenotypes was examined in 909 healthy, adult Brazilians, self-identified as White, Brown or Black ("race/color" categories of the Brazilian census). The cohort was genotyped for CYP3A5*3 (rs776746), CYP3A5*6 (rs10264272) and CYP3A5*7 (rs41303343), CYP3A5 haplotypes were imputed and CYP3A5 metabolizer phenotypes were inferred according to the number of defective CYP3A5 alleles. Estimates of the individual proportions of Amerindian, African and European ancestry were available for the entire cohort. Multinomial log-linear regression models were applied to infer the statistical association between the distribution of CYP3A5 alleles, haplotypes and phenotypes (response variables), and self-reported Color, geographical region and ancestry (explanatory variables). We found that Color per se or in combination with geographical region associates significantly with the distribution of CYP3A5 variant alleles and CYP3A5 metabolizer phenotypes, whereas geographical region per se influences the frequency distribution of CYP3A5 variant alleles. The odds of having the default CYP3A5*3 allele and the poor metabolizer phenotype increases continuously with the increase of European ancestry and decrease of African ancestry. The opposite trend is observed in relation to CYP3A5*6, CYP3A5*7, the default CYP3A5*1 allele, and both the extensive and intermediate phenotypes. No significant effect of Amerindian ancestry on the distribution of CYP3A5 alleles or phenotypes was observed. In conclusion, this study strongly supports the notion that the intrinsic heterogeneity of the Brazilian population must be acknowledged in the design and interpretation of pharmacogenomic studies, and dealt with as a continuous variable, rather than proportioned in arbitrary categories that do not capture the diversity of the population. The relevance of this work extrapolates the Brazilian borders, and extends to other admixed peoples of the Americas, with ancestral roots in Europe, Africa and the American continent.
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Affiliation(s)
| | - Daniela D. Vargens
- Programa de Farmacologia, Instituto Nacional de Câncer, Rio de Janeiro, RJ, Brazil
| | - Ana Beatriz Santoro
- Programa de Farmacologia, Instituto Nacional de Câncer, Rio de Janeiro, RJ, Brazil
| | - Mara H. Hutz
- Departamento de Genética, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | | | - Sérgio D. J. Pena
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | | | - Marco A. Romano-Silva
- Instituto Nacional de Ciência e Tecnologia de Medicina Molecular, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
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Durso DF, Bydlowski SP, Hutz MH, Suarez-Kurtz G, Magalhães TR, Junho Pena SD. Association of genetic variants with self-assessed color categories in Brazilians. PLoS One 2014; 9:e83926. [PMID: 24416183 PMCID: PMC3885524 DOI: 10.1371/journal.pone.0083926] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Accepted: 11/09/2013] [Indexed: 01/07/2023] Open
Abstract
The Brazilian population was formed by extensive admixture of three different ancestral roots: Amerindians, Europeans and Africans. Our previous work has shown that at an individual level, ancestry, as estimated using molecular markers, was a poor predictor of color in Brazilians. We now investigate if SNPs known to be associated with human skin pigmentation can be used to predict color in Brazilians. For that, we studied the association of fifteen SNPs, previously known to be linked with skin color, in 243 unrelated Brazilian individuals self-identified as White, Browns or Blacks from Rio de Janeiro and 212 unrelated Brazilian individuals self-identified as White or Blacks from São Paulo. The significance of association of SNP genotypes with self-assessed color was evaluated using partial regression analysis. After controlling for ancestry estimates as covariates, only four SNPs remained significantly associated with skin pigmentation: rs1426654 and rs2555364 within SLC24A5, rs16891982 at SLC45A2 and rs1042602 at TYR. These loci are known to be involved in melanin synthesis or transport of melanosomes. We found that neither genotypes of these SNPs, nor their combination with biogeographical ancestry in principal component analysis, could predict self-assessed color in Brazilians at an individual level. However, significant correlations did emerge at group level, demonstrating that even though elements other than skin, eye and hair pigmentation do influence self-assessed color in Brazilians, the sociological act of self-classification is still substantially dependent of genotype at these four SNPs.
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Affiliation(s)
- Danielle Fernandes Durso
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Sergio Paulo Bydlowski
- Laboratório de Genética e Hematologia Molecular, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Mara Helena Hutz
- Departamento de Genética, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Guilherme Suarez-Kurtz
- Coordenação de Pesquisa/Divisão de Farmacologia, Instituto Nacional do Câncer (INCA), Rio de Janeiro, RJ, Brazil
| | - Tiago R. Magalhães
- Laboratório de Genômica Clínica, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Sérgio Danilo Junho Pena
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
- Laboratório de Genômica Clínica, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
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Suarez-Kurtz G, Botton MR. Pharmacogenomics of warfarin in populations of African descent. Br J Clin Pharmacol 2013; 75:334-46. [PMID: 22676711 PMCID: PMC3579249 DOI: 10.1111/j.1365-2125.2012.04354.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2012] [Accepted: 05/30/2012] [Indexed: 12/21/2022] Open
Abstract
Warfarin is the most commonly prescribed oral anticoagulant worldwide despite its narrow therapeutic index and the notorious inter- and intra-individual variability in dose required for the target clinical effect. Pharmacogenetic polymorphisms are major determinants of warfarin pharmacokinetic and dynamics and included in several warfarin dosing algorithms. This review focuses on warfarin pharmacogenomics in sub-Saharan peoples, African Americans and admixed Brazilians. These 'Black' populations differ in several aspects, notably their extent of recent admixture with Europeans, a factor which impacts on the frequency distribution of pharmacogenomic polymorphisms relevant to warfarin dose requirement for the target clinical effect. Whereas a small number of polymorphisms in VKORC1 (3673G > A, rs9923231), CYP2C9 (alleles *2 and *3, rs1799853 and rs1057910, respectively) and arguably CYP4F2 (rs2108622), may capture most of the pharmacogenomic influence on warfarin dose variance in White populations, additional polymorphisms in these, and in other, genes (e.g. CALU rs339097) increase the predictive power of pharmacogenetic warfarin dosing algorithms in the Black populations examined. A personalized strategy for initiation of warfarin therapy, allowing for improved safety and cost-effectiveness for populations of African descent must take into account their pharmacogenomic diversity, as well as socio-economical, cultural and medical factors. Accounting for this heterogeneity in algorithms that are 'friendly' enough to be adopted by warfarin prescribers worldwide requires gathering information from trials at different population levels, but demands also a critical appraisal of racial/ethnic labels that are commonly used in the clinical pharmacology literature but do not accurately reflect genetic ancestry and population diversity.
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Affiliation(s)
- Guilherme Suarez-Kurtz
- Divisão de Farmacologia, Coordenação de Pesquisa, Instituto Nacional de Câncer, Rio de Janeiro, Brazil.
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Suarez-Kurtz G, Pena SDJ, Struchiner CJ, Hutz MH. Pharmacogenomic Diversity among Brazilians: Influence of Ancestry, Self-Reported Color, and Geographical Origin. Front Pharmacol 2012; 3:191. [PMID: 23133420 PMCID: PMC3490152 DOI: 10.3389/fphar.2012.00191] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Accepted: 10/16/2012] [Indexed: 11/13/2022] Open
Abstract
BY VIRTUE OF BEING THE PRODUCT OF THE GENETIC ADMIXTURE OF THREE ANCESTRAL ROOTS: Europeans, Africans, and Amerindians, the present-day Brazilian population displays very high levels of genomic diversity, which have important pharmacogenetic/-genomic (PGx) implications. Recognition of this fact has prompted the creation of the Brazilian Pharmacogenomics Network (Refargen), a nationwide consortium of research groups, with the mission to provide leadership in PGx research and education in Brazil, with a population heath impact. Here, we present original data and review published results from a Refargen comprehensive study of the distribution of PGx polymorphisms in a representative cohort of the Brazilian people, comprising 1,034 healthy, unrelated adults, self-identified as white, brown, or black, according to the Color categories adopted by the Brazilian Census. Multinomial log-linear regression analysis was applied to infer the statistical association between allele, genotype, and haplotype distributions among Brazilians (response variables) and self-reported Color, geographical region, and biogeographical ancestry (explanatory variables), whereas Wright's F(ST) statistics was used to assess the extent of PGx divergence among different strata of the Brazilian population. Major PGx implications of these findings are: first, extrapolation of data from relatively well-defined ethnic groups is clearly not applicable to the majority of Brazilians; second, the frequency distribution of polymorphisms in several pharmacogenes of clinical relevance (e.g., ABCB1, CYP3A5, CYP2C9, VKORC) varies continuously among Brazilians and is not captured by race/Color self-identification; third, the intrinsic heterogeneity of the Brazilian population must be acknowledged in the design and interpretation of PGx studies in order to avoid spurious conclusions based on improper matching of study cohorts.
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Affiliation(s)
- Guilherme Suarez-Kurtz
- Programa de Farmacologia, Coordenação de Pesquisa, Instituto Nacional de CâncerRio de Janeiro, Brazil
| | - Sergio Danilo Juno Pena
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas GeraisBelo Horizonte, Brazil
| | | | - Mara Helena Hutz
- Departamento de Genética, Universidade Federal do Rio Grande do SulPorto Alegre, Brazil
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Jakovski K, Kapedanovska Nestorovska A, Labacevski N, J. Dimovski A. Frequency of the most common CYP3A5 polymorphisms in the healthy population of the Republic of Macedonia. MAKEDONSKO FARMACEVTSKI BILTEN 2012. [DOI: 10.33320/maced.pharm.bull.2012.58.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The genetic polymorphism affecting the CYP3A5 enzyme is responsible for inter-individual and interethnic variability in the metabolism of CYP3A5 substrates. The aim of this study was to analyze the distribution of the most common CYP3A5*3 allelic variants in the healthy population of R. Macedonia and to investigate if the allelic frequency falls within the assumed range for European Caucasians. The total of 174 healthy volunteers from the general population were included. The genotyping of the CYP3A5*3 variant alleles, *3A (rs15524) and *3E (rs28365095), was performed with Real-Time PCR based on the allelic discrimination method using a TaqMan SNP genotyping assay according to the manufacturer’s instructions. The CYP3A5*3 allele is abundantly present displaying an allelic frequency of 0.922. We estimate that 0.82 of the Macedonian population are homozygotes for the variant and do not have a CYP3A5 enzymatic activity. Our study demonstrated a high prevalence of CYP3A5*3 allele in the Macedonian population. The distribution of CYP3A5 alleles was similar to that found in other European Caucasians. As the goals of personalized medicine are beginning to be realized, this provides basic
information on the CYP3A5 allele frequency for the future pharmacogenetic research in R. Macedonia.
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Danilovic DLS, Mendes-Correa MC, Lima EU, Zambrini H, K Barros R, Marui S. Correlations of CTLA-4 gene polymorphisms and hepatitis C chronic infection. Liver Int 2012; 32:803-8. [PMID: 22136395 DOI: 10.1111/j.1478-3231.2011.02694.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Revised: 09/28/2011] [Accepted: 10/29/2011] [Indexed: 02/06/2023]
Abstract
BACKGROUND Cytotoxic T lymphocyte-associated factor 4 (CTLA-4) functions as a negative regulator of T cell-mediated immune response. Molecular changes associated to CTLA-4 gene polymorphisms could reduce its ability to suppress and control lymphocyte proliferation. AIMS To evaluate the frequency of CTLA-4 gene polymorphisms in chronic hepatitis C virus (HCV) infected patients and correlate to clinical and histological findings. METHODS We evaluated 112 HCV-infected subjects prospectively selected and 183 healthy controls. Clinical and liver histological data were analysed. -318C > T, A49G and CT60 CTLA-4 single-nucleotide polymorphisms (SNPs) were studied by PCR-RFLP and AT(n) polymorphism by DNA fragment analysis by capillary electrophoresis in automatic sequencer. RESULTS Eight AT repetitions in 3'UTR region were more frequent in HCV-infected subjects. We found a positive association of -318C and + 49G with HCV genotype 3 (P = 0.008, OR 9.13, P = 0.004, OR 2.49 respectively) and an inverse association of both alleles with HCV genotype 1 (P = 0.020, OR 0.19, P = 0.002, OR 0.38 respectively). Allele + 49G was also associated to aminotransferases quotients > 3 (qALT, P = 0.034, qAST, P = 0.041). Allele G of CT60 SNP was also associated with qAST > 3 (P = 0.012). Increased number of AT repetitions was positively associated to severe necroinflammatory activity scores in liver biopsies (P = 0.045, OR 4.62). CONCLUSION CTLA-4 gene polymorphisms were associated to HCV-infection. Eight AT repetitions were more prevalent in HCV-infected subjects. -318C and + 49G alleles were associated to genotypes 1 and 3 infections and increased number of AT repetitions in 3'UTR region favoured severe necroinflammatory activity scores in liver biopsies.
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Affiliation(s)
- Debora L S Danilovic
- Unidade de Tireóide - Laboratório de Endocrinologia Celular e Molecular - LIM 25 Disciplina de Endocrinologia da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.
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Silbiger VN, Hirata MH, Luchessi AD, Genvigir FDV, Cerda A, Rodrigues AC, Willrich MAV, Arazi SS, Dorea EL, Bernik MMS, Faludi AA, Bertolami MC, Santos C, Carracedo A, Salas A, Freire A, Lareu MV, Phillips C, Porras-Hurtado L, Fondevila M, Hirata RDC. Differentiation of African components of ancestry to stratify groups in a case-control study of a Brazilian urban population. Genet Test Mol Biomarkers 2012; 16:524-30. [PMID: 22288895 DOI: 10.1089/gtmb.2011.0267] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND Balancing the subject composition of case and control groups to create homogenous ancestries between each group is essential for medical association studies. METHODS We explored the applicability of single-tube 34-plex ancestry informative markers (AIM) single nucleotide polymorphisms (SNPs) to estimate the African Component of Ancestry (ACA) to design a future case-control association study of a Brazilian urban sample. RESULTS One hundred eighty individuals (107 case group; 73 control group) self-described as white, brown-intermediate or black were selected. The proportions of the relative contribution of a variable number of ancestral population components were similar between case and control groups. Moreover, the case and control groups demonstrated similar distributions for ACA <0.25 and >0.50 categories. Notably a high number of outlier values (23 samples) were observed among individuals with ACA <0.25. These individuals presented a high probability of Native American and East Asian ancestral components; however, no individuals originally giving these self-described ancestries were observed in this study. CONCLUSIONS The strategy proposed for the assessment of ancestry and adjustment of case and control groups for an association study is an important step for the proper construction of the study, particularly when subjects are taken from a complex urban population. This can be achieved using a straight forward multiplexed AIM-SNPs assay of highly discriminatory ancestry markers.
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Affiliation(s)
- Vivian N Silbiger
- Faculty of Pharmaceutical Sciences, University of Sao Paulo, São Paulo, Brazil.
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Suarez-Kurtz G. Pharmacogenomic Applications in the Developing World: The American Continent. ADVANCES IN MICROBIAL ECOLOGY 2012. [DOI: 10.1007/978-1-4614-2182-5_10] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Pharmacogenetics of OATP transporters reveals that SLCO1B1 c.388A>G variant is determinant of increased atorvastatin response. Int J Mol Sci 2011; 12:5815-27. [PMID: 22016628 PMCID: PMC3189752 DOI: 10.3390/ijms12095815] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Revised: 08/29/2011] [Accepted: 08/30/2011] [Indexed: 12/03/2022] Open
Abstract
Aims The relationship between variants in SLCO1B1 and SLCO2B1 genes and lipid-lowering response to atorvastatin was investigated. Material and Methods One-hundred-thirty-six unrelated individuals with hypercholesterolemia were selected and treated with atorvastatin (10 mg/day/4 weeks). They were genotyped with a panel of ancestry informative markers for individual African component of ancestry (ACA) estimation by SNaPshot® and SLCO1B1 (c.388A>G, c.463C>A and c.521T>C) and SLCO2B1 (−71T>C) gene polymorphisms were identified by TaqMan® Real-time PCR. Results Subjects carrying SLCO1B1 c.388GG genotype exhibited significantly high low-density lipoprotein (LDL) cholesterol reduction relative to c.388AA+c.388AG carriers (41 vs. 37%, p = 0.034). Haplotype analysis revealed that homozygous of SLCO1B1*15 (c.521C and c.388G) variant had similar response to statin relative to heterozygous and non-carriers. A multivariate logistic regression analysis confirmed that c.388GG genotype was associated with higher LDL cholesterol reduction in the study population (OR: 3.2, CI95%:1.3–8.0, p < 0.05). Conclusion SLCO1B1 c.388A>G polymorphism causes significant increase in atorvastatin response and may be an important marker for predicting efficacy of lipid-lowering therapy.
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Frequencies and roles of CYP3A5, CYP3A4 and ABCB1 single nucleotide polymorphisms in Italian teenagers after kidney transplantation. Pharmacol Rep 2011; 62:1159-69. [PMID: 21273673 DOI: 10.1016/s1734-1140(10)70378-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2009] [Revised: 05/06/2010] [Indexed: 11/24/2022]
Abstract
The main genes involved in the pharmacokinetics of immunosuppressive drugs are those encoding cytochrome P450 (CYP) family enzymes and multidrug resistance 1 (ABCB1). In this study, 87 Italian teenagers with transplanted kidneys (mean age 11.6 ± 4.8 years) receiving calcineurin inhibitors (CNIs) were genotyped for the single nucleotide polymorphisms (SNPs) CYP3A5*1/3 and CYP3A4*1B for CYP3A, and C1236T, G2677T/A, C3435T and IVS21+49 for ABCB1, and retrospectively evaluated for the influence of the screened SNPs on CNI blood level at different post-transplantation times. The CYP3A5*1 allele was present in 7% of the patients, and the CYP3A4*1B allele was present in 3% of patients. The ABCB1 C1236T, G2677T/A and C3435T SNPs C, G and T occurred frequently (55%, 53% and 54%, respectively). The frequency of the T allele of IVS21+49 was 86%. The frequency of SNPs in both genes was comparable with that reported in other European Caucasian populations but different from that found in Asians or Afro-Americans. None of the cyclosporine (CsA) pharmacokinetic parameters were associated with the CYP3A5 genetic polymorphism, whereas the presence of the A allele in some patients was responsible for the required administration of a significantly increased dose of tacrolimus (Tac) that was necessary to reach therapeutic target levels. None of the Tac pharmacokinetic parameters were associated with ABCB1 SNPs, but ABCB1 SNPs had early effects on the CsA exposure index and dose requirements. In conclusion, because SNPs of the CYP3A and ABCB1 genes may be associated with CNI pharmacokinetic parameters and exposure indices, pre-transplant genetic screening should be considered in order to avoid immunosuppressant-related adverse events.
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Santoro A, Felipe CR, Tedesco-Silva H, Medina-Pestana JO, Struchiner CJ, Ojopi EB, Suarez-Kurtz G. Pharmacogenetics of calcineurin inhibitors in Brazilian renal transplant patients. Pharmacogenomics 2011; 12:1293-303. [PMID: 21806386 DOI: 10.2217/pgs.11.70] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
AIM Polymorphisms in the CYP3A5 and ABCB1 genes have been investigated as modulators of the pharmacokinetics and clinical effects of cyclosporine (CSA) and tacrolimus (TAC) in European, North American and Asian populations, with controversial results. The extensive variation in worldwide frequency distribution of CYP3A5 and ABCB1 polymorphisms is a caveat against the extrapolation of these data to the heterogeneous and admixed Brazilian population. We investigated the effect of CYP3A5 and ABCB1 polymorphisms on CSA and TAC dose-adjusted trough concentration (C₀/dose) in Brazilian renal transplant recipients, during the first 3 months post-transplantation. MATERIALS & METHODS Patients receiving CSA (n = 150) or TAC (n = 151) were genotyped for CYP3A5*3 (rs776746, 6986A>G), *6 (rs10264272, 14690G>A) and *7 (rs41303343, 27131-27132insT) and for ABCB1 1236C>T (rs1128503), 2677G>T/A (rs2032582) and 3435C>T (rs1045642) polymorphisms. We explored the effects of CYP3A5 and ABCB1 polymorphisms, clinical and demographical characteristics on CSA and TAC C₀/dose under a two-step data analysis strategy by fitting a longitudinal mixed-effects model to the data; first to select the important covariates under a univariate setting and then to fit the final multivariate model. RESULTS C₀/dose of TAC was associated with the number of CYP3A5-defective alleles, in a gene-dose manner, throughout the observation period, whereas C₀/dose of CSA was associated with body surface area and prednisone dosing. No other significant associations were detected. CONCLUSION Individual adjustment of the initial TAC dose according to the CYP3A5 haplotypes comprising the CYP3A5*3, *6 and *7 defective alleles might prove beneficial to Brazilian renal transplant recipients and should be further investigated in prospective trials.
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Affiliation(s)
- Ana Santoro
- Divisão de Farmacologia, Coordenação de Pesquisa, Instituto Nacional de Câncer, Rio de Janeiro, RJ 20231-050, Brazil
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Lins TC, Vieira RG, Grattapaglia D, Pereira RW. Population analysis of vitamin D receptor polymorphisms and the role of genetic ancestry in an admixed population. Genet Mol Biol 2011; 34:377-85. [PMID: 21931507 PMCID: PMC3168175 DOI: 10.1590/s1415-47572011000300003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2011] [Accepted: 04/27/2011] [Indexed: 12/04/2022] Open
Abstract
The vitamin D receptor (VDR) is an essential protein related to bone metabolism. Some VDR alleles are differentially distributed among ethnic populations and display variable patterns of linkage disequilibrium (LD). In this study, 200 unrelated Brazilians were genotyped using 21 VDR single nucleotide polymorphisms (SNPs) and 28 ancestry informative markers. The patterns of LD and haplotype distribution were compared among Brazilian and the HapMap populations of African (YRI), European (CEU) and Asian (JPT+CHB) origins. Conditional regression and haplotype-specific analysis were performed using estimates of individual genetic ancestry in Brazilians as a quantitative trait. Similar patterns of LD were observed in the 5′ and 3′ gene regions. However, the frequency distribution of haplotype blocks varied among populations. Conditional regression analysis identified haplotypes associated with European and Amerindian ancestry, but not with the proportion of African ancestry. Individual ancestry estimates were associated with VDR haplotypes. These findings reinforce the need to correct for population stratification when performing genetic association studies in admixed populations.
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Affiliation(s)
- Tulio C Lins
- Programa de Pós-Graduação em Ciências Genômicas e Biotecnologia, Universidade Católica de Brasília, Brasília, DF, Brazil
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Pena SDJ, Di Pietro G, Fuchshuber-Moraes M, Genro JP, Hutz MH, Kehdy FDSG, Kohlrausch F, Magno LAV, Montenegro RC, Moraes MO, de Moraes MEA, de Moraes MR, Ojopi EB, Perini JA, Racciopi C, Ribeiro-Dos-Santos AKC, Rios-Santos F, Romano-Silva MA, Sortica VA, Suarez-Kurtz G. The genomic ancestry of individuals from different geographical regions of Brazil is more uniform than expected. PLoS One 2011; 6:e17063. [PMID: 21359226 PMCID: PMC3040205 DOI: 10.1371/journal.pone.0017063] [Citation(s) in RCA: 417] [Impact Index Per Article: 32.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2010] [Accepted: 01/18/2011] [Indexed: 11/19/2022] Open
Abstract
Based on pre-DNA racial/color methodology, clinical and pharmacological trials have traditionally considered the different geographical regions of Brazil as being very heterogeneous. We wished to ascertain how such diversity of regional color categories correlated with ancestry. Using a panel of 40 validated ancestry-informative insertion-deletion DNA polymorphisms we estimated individually the European, African and Amerindian ancestry components of 934 self-categorized White, Brown or Black Brazilians from the four most populous regions of the Country. We unraveled great ancestral diversity between and within the different regions. Especially, color categories in the northern part of Brazil diverged significantly in their ancestry proportions from their counterparts in the southern part of the Country, indicating that diverse regional semantics were being used in the self-classification as White, Brown or Black. To circumvent these regional subjective differences in color perception, we estimated the general ancestry proportions of each of the four regions in a form independent of color considerations. For that, we multiplied the proportions of a given ancestry in a given color category by the official census information about the proportion of that color category in the specific region, to arrive at a "total ancestry" estimate. Once such a calculation was performed, there emerged a much higher level of uniformity than previously expected. In all regions studied, the European ancestry was predominant, with proportions ranging from 60.6% in the Northeast to 77.7% in the South. We propose that the immigration of six million Europeans to Brazil in the 19th and 20th centuries--a phenomenon described and intended as the "whitening of Brazil"--is in large part responsible for dissipating previous ancestry dissimilarities that reflected region-specific population histories. These findings, of both clinical and sociological importance for Brazil, should also be relevant to other countries with ancestrally admixed populations.
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Affiliation(s)
- Sérgio D J Pena
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
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Suarez-Kurtz G. Pharmacogenetics in the brazilian population. Front Pharmacol 2010; 1:118. [PMID: 21833165 PMCID: PMC3153000 DOI: 10.3389/fphar.2010.00118] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Accepted: 08/27/2010] [Indexed: 12/23/2022] Open
Abstract
Brazil is the fifth largest country in the world and its present population, in excess of 190;million, is highly heterogeneous, as a result of centuries of admixture between Amerindians, Europeans, and Sub-Saharan Africans. The estimated individual proportions of biogeographical ancestry vary widely and continuously among Brazilians: most individuals, irrespective of self-identification as White, Brown or Black - the major categories of the Brazilian Census "race/color" system - have significant degrees of European and African ancestry, while a sizeable number display also Amerindian ancestry. These features have important pharmacogenetic (PGx) implications: first, extrapolation of PGx data from relatively well-defined ethnic groups is clearly not applicable to the majority of Brazilians; second, the frequency distribution of polymorphisms in pharmacogenes (e.g., CYP3A5, CYP2C9, GSTM1, ABCB1, GSTM3, VKORC, etc) varies continuously among Brazilians and is not captured by race/color self-identification; third, the intrinsic heterogeneity of the Brazilian population must be acknowledged in the design and interpretation of PGx studies in order to avoid spurious conclusions based on improper matching of study cohorts. The peculiarities of PGx in Brazilians are illustrated with data for different therapeutic groups, such as anticoagulants, HIV protease inhibitors and non-steroidal antinflammatory drugs, and the challenges and advantages created by population admixture for the study and implementation of PGx are discussed. PGx data for Amerindian groups and Brazilian-born, first-generation Japanese are presented to illustrate the rich diversity of the Brazilian population. Finally, I introduce the reader to the Brazilian Pharmacogenetic Network or Refargen, a nation-wide consortium of research groups, with the mission to provide leadership in PGx research and education in Brazil, with a population health impact.
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Affiliation(s)
- Guilherme Suarez-Kurtz
- Divisão de Farmacologia, Coordenação de Pesquisa, Instituto Nacional de CâncerRio de Janeiro, Brazil
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Suarez-Kurtz G, Amorim A, Damasceno A, Hutz MH, Moraes MOD, Ojopi ÉB, Pena SDJ, Perini JA, Prata MJ, Ribeiro-dos-Santos Â, Romano-Silva MA, Teixeira D, Struchiner CJ. VKORC1 polymorphisms in Brazilians: comparison with the Portuguese and Portuguese-speaking Africans and pharmacogenetic implications. Pharmacogenomics 2010; 11:1257-67. [DOI: 10.2217/pgs.10.89] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Aims: The heterogeneity of the Brazilian population renders the extrapolation of pharmacogenomic data derived from well-defined ethnic groups inappropriate. We investigated the influence of self-reported ‘race/color’, geographical origin and genetic ancestry on the distribution of four VKORC1 SNPs and haplotypes in Brazilians. Comparative data were obtained from two major ancestral roots of Brazilians: Portuguese and Africans from former Portuguese colonies. Materials & methods: A total of 1037 healthy adults Brazilians, recruited at four different geographical regions and self identified as white, brown or black (race/color categories), 89 Portuguese and 216 Africans from Angola and Mozambique were genotyped for the VKORC1 3673G>A (rs9923231), 5808T>G (rs2884737), 6853G>C (rs8050894) and 9041G>A (rs7294) polymorphisms using TaqMan® (Applied Biosystems, CA, USA) assays. VKORC1 haplotypes were statistically inferred using the haplo.stats software. We inferred the statistical association between the distribution of the VKORC1 polymorphisms among Brazilians and self-reported color, geographical region and genetic ancestry by fitting multinomial log linear models via neural networks. Individual proportions of European and African ancestry were used to assess the impact of genetic admixture on the frequency distribution of VKORC1 polymorphisms among Brazilians, and for the comparison of Brazilians with Portuguese and Africans. Results: The frequency distribution of the 3673G>A and 5808T>G polymorphisms, and VKORC1 haplotypes among Brazilians varies across geographical regions, within self-reported color categories and according to the individual proportions of European and African genetic ancestry. Notably, the frequency of the warfarin sensitive VKORC1 3673A allele and the distribution of VKORC1 haplotypes varied continuously as the individual proportion of European ancestry increased in the entire cohort, independently of race/color categorization and geographical origin. Brazilians with more than 80% African ancestry differ significantly from Angolans and Mozambicans in frequency of the 3673G>A, 5808T>G and 6853G>C polymorphisms and haplotype distribution, whereas no such differences are observed between Brazilians with more than 90% European ancestry and Portuguese individuals. Conclusion: The diversity of the Brazilian population, evident in the distribution of VKORC1 polymorphisms, must be taken into account in the design of pharmacogenetic clinical trials and dealt with as a continuous variable. Warfarin dosing algorithms that include ‘race’ terms defined for other populations are clearly not applicable to the heterogeneous and extensively admixed Brazilian population.
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Affiliation(s)
| | - António Amorim
- Institute of Molecular Pathology & Immunology of the University of Porto (IPATIMUP), Porto, Portugal and Departamento de Biologia, Faculdade de Ciências da Universidade do Porto, Porto, Portugal
| | - Albertino Damasceno
- Serviço de Cardiologia, Faculdade de Medicina, Universidade Eduardo Mondlane, Maputo, Mozambique
| | - Mara H Hutz
- Departamento de Genética, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Manuel Odorico de Moraes
- Unidade de Farmacologia Clínica, Departamento de Fisiologia e Farmacologia, Faculdade de Medicina da Universidade Federal do Ceará, Fortaleza, CE, Brazil
| | - Élida B Ojopi
- Laboratório de Neurociências (LIM-27), Instituto de Psiquiatria, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Sérgio DJ Pena
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil and GENE – Núcleo de Genética Médica, Belo Horizonte, MG, Brazil
| | - Jamila A Perini
- Divisão de Farmacologia, Instituto Nacional do Câncer, Rio de Janeiro, RJ, Brazil
| | - Maria João Prata
- Institute of Molecular Pathology & Immunology of the University of Porto (IPATIMUP), Porto, Portugal and Departamento de Biologia, Faculdade de Ciências da Universidade do Porto, Porto, Portugal
| | | | - Marco A Romano-Silva
- Instituto Nacional de Ciência e Tecnologia de Medicina Molecular, Laboratório de Neurociência, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Daniel Teixeira
- Institute of Molecular Pathology & Immunology of the University of Porto (IPATIMUP), Porto, Portugal and Departamento de Biologia, Faculdade de Ciências da Universidade do Porto, Porto, Portugal
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Tedesco-Silva H, Felipe CR, Park SI, Pinheiro-Machado PG, Garcia R, Slade A, Schmouder R, Medina-Pestana JO. Randomized crossover study to assess the inter- and intrasubject variability of morning mycophenolic acid concentrations from enteric-coated mycophenolate sodium and mycophenolate mofetil in stable renal transplant recipients. Clin Transplant 2010; 24:E116-23. [DOI: 10.1111/j.1399-0012.2009.01183.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Teixeira AG, Silva AS, Lin FLH, Velletri R, Bavia L, Belfort R, Isaac L. Association of complement factor H Y402H polymorphism and age-related macular degeneration in Brazilian patients. Acta Ophthalmol 2010; 88:e165-9. [PMID: 20626361 DOI: 10.1111/j.1755-3768.2010.01932.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE The aim of this study was investigate the association between complement Factor H polymorphism (Y402H) and age-related macular degeneration (AMD) in Brazilian patients. METHODS Patients with AMD aged 50 or more and age-matched healthy controls were enrolled in the study. Genomic DNA was isolated from leucocytes of patients and controls; the Y402H polymorphism of complement Factor H gene (CFH) was determined by polymerase chain reaction directed sequencing. RESULTS The frequency of 1277C allele of Factor H was 56.30% in patients with AMD compared with 36.51% in controls (p-value=0.001). The genotypic distribution differed significantly between the two groups (1277CC 36.98%, 1277CT 38.65% and 1277TT 24.37% for AMD group; 1277CC 13.16%, 1277CT 46.71% and 1277TT 40.13% for controls, p-value=0.001). The odds ratio for patients with AMD carrying only one 1277C allele was 1.36 and for those carrying two 1277C alleles was 4.63, when compared to the control group. CONCLUSIONS These results suggest the Y402H polymorphism of CFH is a risk factor to the development of AMD in Brazilian patients. This is in accordance with findings from the majority of previous study population in Europe and North American.
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Affiliation(s)
- Anderson G Teixeira
- Department of Ophthalmology, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil
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Cerda A, Genvigir FDV, Arazi SS, Hirata MH, Dorea EL, Bernik MMS, Bertolami MC, Faludi AA, Hirata RDC. Influence of SCARB1 polymorphisms on serum lipids of hypercholesterolemic individuals treated with atorvastatin. Clin Chim Acta 2010; 411:631-7. [PMID: 20064494 DOI: 10.1016/j.cca.2010.01.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2009] [Revised: 10/12/2009] [Accepted: 01/04/2010] [Indexed: 01/17/2023]
Abstract
BACKGROUND The SR-BI is a key component on the cholesterol metabolism. Polymorphisms in the SR-BI gene (SCARB1) were related with variations on plasma lipoprotein profile and other risk factors for cardiovascular disease. We tested the relationship of 3 SCARB1 single nucleotide polymorphisms (SNPs) with hypercholesterolemia in a Brazilian population and whether these variants can influence lipid-lowering response to atorvastatin. METHODS c.4G>A, c.726+54C>T and c.1050C>T SNPs and serum concentrations of lipid and apolipoproteins were evaluated in 147 hypercholesterolemic (HC) and 185 normolipidemic (NL) unrelated Brazilian subjects. HC patients were treated with atorvastatin (10 mg/day/4 weeks). RESULTS Frequencies of SCARB1 polymorphisms were similar between the HC and NL groups (p>0.05). The T allele for c.726+54C>T was associated with higher LDL-c in NL and with higher apoB and apoB/apoAI in HC (p<0.05). HC individuals carrying c.1050C allele carriers (CC and CT genotypes) had lower change of total cholesterol, LDL-c, apoB and apoB/apoAI ratio (p<0.05) than the TT genotype carriers in response to atorvastatin. CONCLUSION The SCARB1 polymorphisms are related with variations in serum lipids in the Brazilian population and c.1050C>T SNP is associated with lipid-lowering atorvastatin response.
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Affiliation(s)
- Alvaro Cerda
- Department of Clinical and Toxicological Analysis, School of Pharmaceutical Sciences, University of Sao Paulo, Sao Paulo, SP, Brazil.
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Duconge J, Ruaño G. The Emerging Role of Admixture in the Pharmacogenetics of Puerto Rican Hispanics. ACTA ACUST UNITED AC 2010; 1. [PMID: 23227441 DOI: 10.4172/2153-0645.1000101] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Admixture is of great relevance to the clinical application of pharmacogenetics and personalized medicine. Preliminary findings in Puerto Ricans further substantiate the argument for admixture as a critical covariate in a customized DNA-guided warfarin dosing algorithm. To this purpose, a genome-wide approach that incorporates admixture as an independent predictor of dose variability in DNA-guided algorithms has been postulated. Admixture is expected to be able to reveal some relevant associations in the genetic epidemiology of Hispanics and will be indispensable to assure that pharmacogenomic research can be pursued in such mixed populations. Consequently, the clinical utility of knowing an individual's genotype before initiating drug treatment in Puerto Ricans, and Hispanics in general, will finally be untangled by developing a "Genetic Prescription Model" that takes admixture into consideration. This approach will help lead physicians and patients to their desired treatment goal, resulting in more effective healthcare in admixed people.
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Affiliation(s)
- Jorge Duconge
- University of Puerto Rico School of Pharmacy, Medical Sciences Campus, Pharmaceutical Sciences Department, San Juan PR 00936
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Willrich MAV, Hirata MH, Hirata RDC. Statin regulation of CYP3A4 and CYP3A5 expression. Pharmacogenomics 2009; 10:1017-24. [PMID: 19530969 DOI: 10.2217/pgs.09.42] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
CYP3A4 and CYP3A5 are cytochrome P450 enzymes that are highly expressed in the liver and gut and metabolize endogenous compounds and xenobiotics. Statins are cholesterol-lowering drugs that are extensively metabolized by CYP3A4 and CYP3A5. The bioavailability of statins is affected by CYP3A4 and CYP3A5 and glucuronidases metabolism as well as uptake and efflux transporters that affect drug disposition. CYP3A4 and CYP3A5 variants have been demonstrated to influence the pharmacokinetics, efficacy and safety of statins. Inducers and inhibitors of CYP3A4 and CYP3A5 play an important role in reducing statin efficacy and increase the risk of adverse effects, respectively. Statins have been demonstrated to increase CYP3A expression in vitro, most likely because they are ligands to nuclear receptors (pregnane X receptor and constitutive androsterone receptor) that form heterodimers with retinoid X receptors and bind to responsive elements in the CYP3A4 and CYP3A5 promoter regions. This special report outlines the earlier studies on variability of response to statins owing to CYP3A variants and highlights findings on the induction of CYP3A4 and CYP3A5 expression by statins.
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Affiliation(s)
- Maria Alice Vieira Willrich
- Department of Clinical and Toxicological Analysis, University of Sao Paulo, Avenue Prof. Lineu Prestes, 580, B17, 05508-05900 Sao Paulo, SP, Brazil.
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Gonzalez-Covarrubias V, Zhang J, Kalabus JL, Relling MV, Blanco JG. Pharmacogenetics of human carbonyl reductase 1 (CBR1) in livers from black and white donors. Drug Metab Dispos 2008; 37:400-7. [PMID: 19022938 DOI: 10.1124/dmd.108.024547] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Carbonyl reductase 1 (CBR1) reduces the anticancer drug doxorubicin into the cardiotoxic metabolite doxorubicinol. We documented the hepatic expression of CBR1 in samples from white and black donors. Concordance between ethnicity and geographical ancestry was examined with ancestry informative markers. Livers from blacks and whites showed similar CBR1 mRNA levels (CBR1 mRNA(blacks) = 4.8 +/- 4.3 relative -fold versus CBR1 mRNA(whites) = 3.6 +/- 3.6 relative -fold; p = 0.217). CBR1 protein levels did not differ between both groups (CBR1(blacks) = 8.0 +/- 3.4 nmol/g cytosolic protein versus CBR1(whites) = 9.0 +/- 4.6 nmol/g cytosolic protein; p = 0.347). The CBR1 3'-untranslated region polymorphism 1096G>A was detected in DNA samples from whites (p = 0.875; q = 0.125), and livers with homozygous G/G genotypes showed a trend toward higher CBR1 mRNA levels compared with samples with heterozygous G/A genotypes [CBR1 1096G>A((G/G)) = 4.1 +/- 4.1 relative -fold versus CBR1 1096G>A((G/A)) = 3.0 +/- 2.5 relative-fold; p = 0.266]. CBR1 1096G>A genotype status was associated with CBR1 protein levels (p = 0.030) and CBR activity expressed as the rate of synthesis of doxorubicinol (p = 0.028). Our findings warrant further studies to evaluate the impact of CBR1 1096G>A genotype status on the variable pharmacodynamics of anthracycline drugs.
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Affiliation(s)
- Vanessa Gonzalez-Covarrubias
- Department of Pharmaceutical Sciences, The State University of New York at Buffalo, 545 Cooke Hall, Buffalo, NY 14260-1200, USA
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Pharmacogenetics of warfarin: development of a dosing algorithm for brazilian patients. Clin Pharmacol Ther 2008; 84:722-8. [PMID: 18754001 DOI: 10.1038/clpt.2008.166] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
A dosing algorithm including genetic (VKORC1 and CYP2C9 genotypes) and nongenetic factors (age, weight, therapeutic indication, and cotreatment with amiodarone or simvastatin) explained 51% of the variance in stable weekly warfarin doses in 390 patients attending an anticoagulant clinic in a Brazilian public hospital. The VKORC1 3673G>A genotype was the most important predictor of warfarin dose, with a partial R(2) value of 23.9%. Replacing the VKORC1 3673G>A genotype with VKORC1 diplotype did not increase the algorithm's predictive power. We suggest that three other single-nucleotide polymorphisms (SNPs) (5808T>G, 6853G>C, and 9041G>A) that are in strong linkage disequilibrium (LD) with 3673G>A would be equally good predictors of the warfarin dose requirement. The algorithm's predictive power was similar across the self-identified "race/color" subsets. "Race/color" was not associated with stable warfarin dose in the multiple regression model, although the required warfarin dose was significantly lower (P = 0.006) in white (29 +/- 13 mg/week, n = 196) than in black patients (35 +/- 15 mg/week, n = 76).
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CYP3A53A allele is associated with reduced lowering-lipid response to atorvastatin in individuals with hypercholesterolemia. Clin Chim Acta 2008; 398:15-20. [PMID: 18727922 DOI: 10.1016/j.cca.2008.07.032] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2008] [Revised: 07/29/2008] [Accepted: 07/31/2008] [Indexed: 11/23/2022]
Abstract
BACKGROUND The cytochrome P450 isoenzyme 3A5 (CYP3A5) has an important role on biotransformation of xenobiotics. CYP3A5 SNPs have been associated with variations on enzyme activity that can modify the metabolism of several drugs. METHODS In order to evaluate the influence of CYP3A5 variants on response to lowering-cholesterol drugs, 139 individuals with hypercholesterolemia were selected. After a wash-out period of 4 weeks, individuals were treated with atorvastatin (10 mg/day/4 weeks). Genomic DNA was extracted by a salting-out procedure. CYP3A5*3C, CYP3A5*6 and CYP3A5*1D were analyzed by PCR-RFLP and DNA sequencing. RESULTS >Frequencies of the CYP3A5*3C and CYP3A5*1D alleles were lower in individuals of African descent (*3C: 47.8% and *1D: 55.2%) than in non-Africans (*3C: 84.9% and *1D 84.8%, p<0.01). Non-Africans carrying *3A allele (*3C and *1D combined alleles) had lower total and LDL-cholesterol response to atorvastatin than non-*3A allele carriers (p<0.05). CONCLUSION CYP3A5*3A allele is associated with reduced cholesterol-lowering response to atorvastatin in non-African individuals.
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Estrela RCE, Ribeiro FS, Carvalho RS, Gregório SP, Dias-Neto E, Struchiner CJ, Suarez-Kurtz G. Distribution of ABCB1 polymorphisms among Brazilians: impact of population admixture. Pharmacogenomics 2008; 9:267-76. [PMID: 18303963 DOI: 10.2217/14622416.9.3.267] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
INTRODUCTION Interethnic admixture is a source of cryptic population structure that may lead to spurious genotype-phenotype associations in pharmacogenomic studies. We studied the impact of population stratification on the distribution of ABCB1 polymorphisms (1236C>T, 2677G>T/A and 3435C>T) among Brazilians, a highly admixed population with Amerindian, European and African ancestral roots. METHODS Individual DNA from 320 healthy adults was genotyped with a panel of ancestry informative markers, and the proportions of African component of ancestry (ACA) were estimated. ABCB1 genotypes were determined by the single base extension/termination method. We describe the association between ABCB1 polymorphisms and ACA by fitting a linear proportional odds logistic regression model to the data. RESULTS The distribution of the ABCB1 2677G>T/A and 3435C>T, but not the 1236C>T, SNPs displayed a significant trend for decreasing frequency of the T alleles and TT genotypes from White to Intermediate to Black individuals. The same trend was observed in the frequency of the T/nonG/T haplotype at the 1236, 2677 and 3435 loci. When the population sample was proportioned in quartiles, according to the individual ACA estimates, the frequency of the T allele and TT genotype at each locus declined progressively from the lowest (< 0.25 ACA) to the highest (> 0.75 ACA) quartile. Linear proportional odds logistic regression analysis confirmed that the odds of having the T allele at each locus decreases in a continuous manner with the increase of the ACA, throughout the ACA range (0.13-0.94) observed in the overall population sample. A significant association was also detected between the individual ACA estimates and the presence of the T/nonG/T haplotype in the overall population. CONCLUSION Self-identification according to the racial/color categories proposed by the Brazilian Census is insufficient to properly control for population stratification in pharmacogenomic studies of ABCB1.
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Affiliation(s)
- Rita C E Estrela
- Divisão de Farmacologia, Instituto Nacional de Câncer, Rua André Cavalcanti 37, Rio de Janeiro 21230-050, Brazil
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Estrela RCE, Santoro AB, Barroso PF, Tuyama M, Suarez-Kurtz G. CYP3A5 Genotype Has No Impact on Plasma Trough Concentrations of Lopinavir and Ritonavir in HIV-infected Subjects. Clin Pharmacol Ther 2008; 84:205-7. [DOI: 10.1038/clpt.2008.12] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Distribution of the GNB3 825C>T polymorphism among Brazilians: impact of population structure. Eur J Clin Pharmacol 2007; 64:253-6. [DOI: 10.1007/s00228-007-0413-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2007] [Accepted: 11/06/2007] [Indexed: 11/26/2022]
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