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Shriyan B, Mehta P, Patil A, Jadhav S, Kumar S, Puri AS, Govalkar R, Krishnamurthy MN, Punatar S, Gokarn A, Khattry N, Gota V. Role of ADME gene polymorphisms on imatinib disposition: results from a population pharmacokinetic study in chronic myeloid leukaemia. Eur J Clin Pharmacol 2022; 78:1321-1330. [PMID: 35652931 DOI: 10.1007/s00228-022-03345-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 05/24/2022] [Indexed: 11/29/2022]
Abstract
PURPOSE Imatinib is a substrate of CYP3A4, ABCB1 and ABCG2, and is known to have wide variability in pharmacokinetics (PK). At the same time, a clear relationship between drug levels and response also exists for imatinib in chronic myeloid leukaemia (CML). Therefore, pharmacogenetic-based dosing of imatinib is an attractive proposition. This study aims to characterize the population pharmacokinetics of imatinib in order to identify significant covariates including pharmacogenetic variants. METHODS Forty-nine patients with CML were enrolled in the study after being on imatinib for at least 4 consecutive weeks. Steady-state pharmacokinetic sampling was performed either in a sparse (4 samples each, n = 44) or intensive manner (9 samples each, n = 5). An additional pharmacogenetic sample was also collected from all patients. Plasma imatinib levels were estimated using a validated HPLC method. Pharmacogenetic variants were identified using the PharmacoScan array platform. Population pharmacokinetic analysis was carried out using NONMEM v7.2. Seven SNPs within CYP3A4, ABCB1 and ABCG2 genes were evaluated for covariate effect on the clearance of imatinib. RESULTS Imatinib PK was well characterized using a one-compartment model with zero-order absorption. The clearance and volume of distribution were found to be 10.2 L/h and 389 L respectively. Only SNP rs1128503 of the ABCB1 gene had a small but insignificant effect on imatinib clearance, with a 25% reduction in clearance observed in patients carrying the polymorphism. Twenty-three out of forty-nine patients (47%) carried the polymorphic allele, of whom 17 were heterozygous and six were homozygous. CONCLUSION Our study conclusively proves that genetic polymorphisms in the CYP3A4 and ABC family of transporters do not have any role in the personalized dosing of imatinib in CML.
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Affiliation(s)
- Bharati Shriyan
- Department of Clinical Pharmacology, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi Mumbai, 410210, India
| | - Parsshava Mehta
- Department of Clinical Pharmacology, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi Mumbai, 410210, India
| | - Anand Patil
- Department of Clinical Pharmacology, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi Mumbai, 410210, India
| | - Shraddha Jadhav
- Department of Clinical Pharmacology, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi Mumbai, 410210, India
| | - Sharath Kumar
- Department of Clinical Pharmacology, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi Mumbai, 410210, India
| | - Apeksha S Puri
- Department of Clinical Pharmacology, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi Mumbai, 410210, India
| | - Ravina Govalkar
- Department of Clinical Pharmacology, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi Mumbai, 410210, India.,Gahlot Institute of Pharmacy, Koparkhairane, Navi Mumbai, 400709, India
| | - Manjunath Nookala Krishnamurthy
- Department of Clinical Pharmacology, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi Mumbai, 410210, India.,Homi Bhabha National Institute, Mumbai, 400094, India
| | - Sachin Punatar
- Department of Medical Oncology, Tata Memorial Hospital, Mumbai, 400012, India.,Homi Bhabha National Institute, Mumbai, 400094, India
| | - Anant Gokarn
- Department of Medical Oncology, Tata Memorial Hospital, Mumbai, 400012, India.,Homi Bhabha National Institute, Mumbai, 400094, India
| | - Navin Khattry
- Department of Medical Oncology, Tata Memorial Hospital, Mumbai, 400012, India.,Homi Bhabha National Institute, Mumbai, 400094, India
| | - Vikram Gota
- Department of Clinical Pharmacology, Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Navi Mumbai, 410210, India. .,Homi Bhabha National Institute, Mumbai, 400094, India.
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Wang T, Zhou Y, Cao G. Pharmacogenetics of tamoxifen therapy in Asian populations: from genetic polymorphism to clinical outcomes. Eur J Clin Pharmacol 2021; 77:1095-1111. [PMID: 33515076 DOI: 10.1007/s00228-021-03088-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 01/11/2021] [Indexed: 12/15/2022]
Abstract
BACKGROUND Compared with western countries, Asian breast cancer patients have unique pathological and biological characteristics. Most of them are premenopausal women with HR positive. Tamoxifen as the first-line drug for premenopausal women with HR+ is involved in multiple enzymes and transporters during metabolizing and transporting process. Variants that cause decreased or inactive gene products leading to abnormal responses in tamoxifen therapy have well been studied in western countries, whereas such information is much less reported in Asian populations. OBJECTIVE In order to elucidate the relationship between genetic variants and tamoxifen-induced individual drug reactions in different Asian populations and further identify genotypes/phenotypes with potential therapeutic significance. METHODS We reviewed the frequencies of genetic variants in major enzymes and transporter genes involved in the metabolism and transport of tamoxifen across Asian populations as well as significant correlations between genotypes/metabolic phenotypes and metabolites concentrations or BC clinical outcomes. RESULTS Significant inter-ethnic differences in allele frequencies was found among Asian populations, such as CYP2D6*4, *10, *41, CYP2C9*2, ABCB1 C3435T and SLCO1B1*5, and CYP2D6*10/*10 is the most common genotype correlated with adverse clinical outcomes. Moreover, we summarized the barriers and controversies of implementing pharmacogenetics in tamoxifen therapy and concluded that more population-specific pharmacogenetic studies are needed in the future. CONCLUSION This review revealed more systematic pharmacogenomics of genes involved in the metabolism and transport besides CYP2D6, are required to optimize the genotyping strategies and guide the personalized tamoxifen therapy in Asian populations.
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Affiliation(s)
- Tingyu Wang
- College of Pharmacy, Hubei University of Chinese Medicine, Wuhan, 430065, China
| | - Yitian Zhou
- Department of Physiology and Pharmacology, Karolinska Institutet, 17177, Stockholm, Sweden
| | - Guosheng Cao
- College of Pharmacy, Hubei University of Chinese Medicine, Wuhan, 430065, China.
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Dagenais R, Wilby KJ, Elewa H, Ensom MHH. Impact of Genetic Polymorphisms on Phenytoin Pharmacokinetics and Clinical Outcomes in the Middle East and North Africa Region. Drugs R D 2017; 17:341-361. [PMID: 28748348 PMCID: PMC5629135 DOI: 10.1007/s40268-017-0195-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Genetic polymorphisms are known to influence outcomes with phenytoin yet effects in the Middle East and North Africa region are poorly understood. OBJECTIVES The objective of this systematic review was to evaluate the impact of genetic polymorphisms on phenytoin pharmacokinetics and clinical outcomes in populations originating from the Middle East and North Africa region, and to characterize genotypic and allelic frequencies within the region for genetic polymorphisms assessed. METHODS MEDLINE (1946-3 May, 2017), EMBASE (1974-3 May, 2017), Pharmacogenomics Knowledge Base, and Public Health Genomics Knowledge Base online databases were searched. Studies were included if genotyping and analyses of phenytoin pharmacokinetics were performed in patients of the Middle East and North Africa region. Study quality was assessed using a National Institutes of Health assessment tool. A secondary search identified studies reporting genotypic and allelic frequencies of assessed genetic polymorphisms within the Middle East and North Africa region. RESULTS Five studies met the inclusion criteria. CYP2C9, CYP2C19, and multidrug resistance protein 1 C3435T variants were evaluated. While CYP2C9*2 and *3 variants significantly reduced phenytoin metabolism, the impacts of CYP2C19*2 and *3 variants were unclear. The multidrug resistance protein 1 CC genotype was associated with drug-resistant epilepsy, but reported impacts on phenytoin pharmacokinetics were conflicting. Appreciable variability in minor allele frequencies existed both between and within countries of the Middle East and North Africa region. CONCLUSIONS CYP2C9 decrease-of-function alleles altered phenytoin pharmacokinetics in patients originating from the Middle East and North Africa region. The impacts of CYP2C19 and multidrug resistance protein 1 C3435T variants on phenytoin pharmacokinetic and clinical outcomes are unclear and require further investigation. Future research should focus on the clinical outcomes associated with phenytoin therapy. PROSPERO 2017: CRD42017057850.
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Affiliation(s)
- Renée Dagenais
- Faculty of Pharmaceutical Sciences, Pharmaceutical Sciences Building, University of British Columbia, Vancouver, BC, Canada
| | - Kyle John Wilby
- College of Pharmacy, Qatar University, PO Box 2713, Doha, Qatar.
| | - Hazem Elewa
- College of Pharmacy, Qatar University, PO Box 2713, Doha, Qatar
| | - Mary H H Ensom
- Faculty of Pharmaceutical Sciences, Pharmaceutical Sciences Building, University of British Columbia, Vancouver, BC, Canada
- Department of Pharmacy, Children's and Women's Health Centre of British Columbia, Vancouver, BC, Canada
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Phuthong S, Settheetham-Ishida W, Natphopsuk S, Settheetham D, Ishida T. Haplotype Analysis of MDR1 and Risk for Cervical Cancer in Northeastern Thailand. Asian Pac J Cancer Prev 2017; 18:1815-1819. [PMID: 28749110 PMCID: PMC5648384 DOI: 10.22034/apjcp.2017.18.7.1815] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Objective: The aim of this study was to investigate the association between genotype and haplotype of MDR1
(C1236T, G2677T/A and C3435T) and the risk for cervical cancer in Northeastern Thai women. Methods: An
age-matched case-control study involving squamous cell cervical cancer (SCCA) patients (n=204) and healthy controls
(n=204) was enrolled for MDR1 genotyping by real-time PCR method. Results: The genotype distribution of MDR1 in
both patients and controls was not significantly different (p>0.05). The haplotype analysis showed that T-T-T was the
most common haplotype in this population. Significantly increased risk of cervical cancer was observed in carriers of
T-T-C and C-G-T haplotypes with ORs of 1.86 (95%CI=1.02-3.39, p=0.0416) and 2.00 (95%CI=1.18-3.40, p=0.0140),
respectively. Analysis of 2677-3435 haplotype showed increased risk for cervical cancer in G-T (OR=1.55; 95%
CI=1.12-2.13, p=0.0432) and T-C (OR=1.91; 95%CI=1.05-3.47, p=0.0325). Conclusion: The results provide evidence
that haplotype of MDR1 may be an important risk factor for cervical cancer development in Northeastern Thai women.
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Affiliation(s)
- Sophida Phuthong
- Department of Physiology, HPV and EBV and Carcinogenesis Research Group, Faculty of Medicine, Khon Kaen University, Khon Kaen , Thailand.
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Rustemoglu A, Gumus-Akay G, Karakus N, Yigit S, Sahin S, Tasliyurt T. Association analysis of three ABCB1 (MDR1) gene variants (C1236T, G2677A/T and C3435T) and their genotype/haplotype combinations with the familial Mediterranean fever. Xenobiotica 2014; 44:933-40. [PMID: 24773260 DOI: 10.3109/00498254.2014.915071] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
1. Familial Mediterranean fever (FMF) is considered an autosomal recessive disorder, associated with a single gene named Mediterranean fever (MEFV). The aim of this study was to perform genotyping and haplotyping analysis of the multidrug resistance (ATP-binding cassette, subfamily B, member 1 - ABCB1) gene in FMF patients. 2. Three ABCB1 gene polymorphisms (C1236T, G2677T/A and C3435T) were analyzed in 309 FMF patients and 250 healthy control subjects. All subjects were genotyped by PCR-restriction fragment length polymorphism analysis, and statistical analysis was performed using the Arlequin 3.1.1 and SPSS 16.0 software packages. 3. The CT genotype frequency of the C3435T polymorphism (p = 0.003), the CT-GT-CT (C1236T-G2677T/A-C3435T) triple genotype (p = 0.001) and the C-G (C1236T-G2677T/A) haplotype (p = 0.030) were more common in the FMF patients. The CT-GG-CC triple genotype and T-G-C, C-T-T and T-G-T haplotypes (C1236T-G2677T/A-C3435T) were higher in the control subjects (p = 0.011, 0.001, 0.009 and 0.000, respectively). The CT-GG binary genotype and C-T and T-G haplotypes for C1236T-G2677T/A polymorphisms may have a high degree of protective effect against FMF (p = 0.0005, 0.002 and 0.000, respectively). 4. Our study showed that genotypes and haplotypes of ABCB1 gene polymorphisms may affect patients' FMF susceptibility.
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Affiliation(s)
- Aydin Rustemoglu
- Department of Medical Biology, Faculty of Medicine, Gaziosmanpasa University , Tokat , Turkey
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Kassogue Y, Dehbi H, Nassereddine S, Quachouh M, Nadifi S. Genotype variability and haplotype frequency of MDR1 (ABCB1) gene polymorphism in Morocco. DNA Cell Biol 2013; 32:582-8. [PMID: 23930592 DOI: 10.1089/dna.2013.2108] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The multidrug resistance gene (MDR1) plays an important role in the transport of a wide range of drugs and elimination of xenobiotics from the body. Identification of polymorphisms and haplotypes in the MDR1 gene might not only help understand pharmacokinetics and pharmacodynamics of drugs, but also can help in the prediction of drug responses, toxicity, and side effects, especially, in the era of personalized medicine. We have analyzed the genotypic and haplotypic frequencies of the three most common single-nucleotide polymorphisms in the MDR1 gene in a sample of 100 unrelated healthy Moroccan subjects by polymerase chain reaction-restrictive fragment length polymorphism. The observed genotype frequencies were 43% for 1236CC, 49% for 1236CT, and 8% for 1236TT in exon 12; 49% for 2677GG, 47% for 2677GT, and 4% for 2677TT in exon 21; 39% for 3435CC, 51% 3435CT for 3435TT, and 10% for 3435TT in exon 26, respectively. We found that all polymorphisms were in Hardy-Weinberg equilibrium. Moderate linkage disequilibrium (LD) was observed between the three polymorphisms, the strongest LD in our study has been observed between C1236T and G2677T (D'=0.76; r(2)=0.45). We identified eight haplotypes, the most frequent were 1236C-2677G-3435C (53%), 1236T-2677T-3435T (21%), and 1236C-2677G-3435T (10%), respectively. Our findings might facilitate future studies on pharmacokinetics of P-glycoprotein substrate drugs and interindividual variability to drugs in Moroccan patients.
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Affiliation(s)
- Yaya Kassogue
- 1 Genetics and Molecular Pathology Laboratory, Medical School of Casablanca, University Hassan II , Casablanca, Morocco
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Ozdemir S, Uludag A, Silan F, Atik SY, Turgut B, Ozdemir O. Possible Roles of the Xenobiotic Transporter P-glycoproteins Encoded by the MDR1 3435 C>T Gene Polymorphism in Differentiated Thyroid Cancers. Asian Pac J Cancer Prev 2013; 14:3213-7. [DOI: 10.7314/apjcp.2013.14.5.3213] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Özhan G, Kara M, Sari FM, Yanar HT, Ercan G, Alpertunga B. Associations between the functional polymorphisms in the ABCB1 transporter gene and colorectal cancer risk: a case-control study in Turkish population. Toxicol Mech Methods 2013. [PMID: 23193993 DOI: 10.3109/15376516.2012.743639] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Colorectal cancer is among the most common cancer types in the world and its etiology involves the interaction of genetic and environmental factors. ABCB1 is highly expressed in the apical surface of colonic epithelial cells and acts as an efflux pump by transporting toxic endogenous substances, drugs and xenobiotics out of cells. ABCB1 polymorphisms may either change its protein expression or alter its function. Several studies have reported a possible association between ABCB1 variants and colorectal cancer, but no consistent conclusion has been arrived at. Therefore, we aimed to investigate the relationship between colorectal cancer and the functional common variants of ABCB1 (1236C > T; 2677G > T/A; 3435C > T). The distributions of the variants were determined in 103 patients with colorectal cancer and 150 healthy volunteers using polymerase chain reaction-restriction fragment length polymorphism methods. ABCB1 1236C > T was statistically significantly associated with colorectal cancer risk (OR, odd ratio = 1.91; 95% CI, confidence interval = 1.09-3.35; p = 0.034). In haplotype-based analysis, the proportion of individuals with the ABCB1 haplotype C1236-G2677-T3435 was significantly more common in patients than in controls (OR = 11.96; 95% CI = 2.59-55.32; p = 0.0004). We believe that the findings may be beneficial to the development of efficacious preventive strategies and therapies for colorectal cancer.
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Affiliation(s)
- Gül Özhan
- Department of Pharmaceutical Toxicology, Faculty of Pharmacy, Istanbul University, 34116 Beyazit, Istanbul, Turkey.
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Singh AB, Bousman CA, Ng CH, Byron K, Berk M. ABCB1 polymorphism predicts escitalopram dose needed for remission in major depression. Transl Psychiatry 2012; 2. [PMID: 23188198 PMCID: PMC3565756 DOI: 10.1038/tp.2012.115] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
The ATP-binding cassette family of transporter proteins, subfamily B (MDR/TAP), member 1 (ABCB1) (P-glycoprotein) transporter is a key component of the blood-brain barrier. Many antidepressants are subject to ABCB1 efflux. Functional polymorphisms of ABCB1 may influence central nervous system bioavailability of antidepressants subject to efflux. Single-nucleotide polymorphisms (SNPs) at rs1045642 (C3435T) of ABCB1 have been associated with efflux pump efficiency. This may explain part of the interindividual variation in antidepressant dose needed to remit. Individuals (N=113) with DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition) major depressive disorder (MDD) were treated with escitalopram (ESC) or venlafaxine (VEN) over 8 weeks. The17-item Hamilton Depression Rating Scale was assessed serially, blind to genotype. SNP rs1045642 of ABCB1 along with two SNPs previously reported to be in linkage disequilibrium with it (rs2032582 and rs1128503) were genotyped. Demographic features, clinical features, P450 metabolizer status and 5-HTTLPR (serotonin-transporter-linked promoter region) genotype were controlled for. Carriers of rs1045642 TT needed on average 11 mg of ESC to remit, whereas TC and CC carriers required 24 and 19 mg, respectively (P=0.0001). This equates to a 2.0- (95% confidence interval=1.5-3.4; P<0.001) fold greater ESC dose needed to remit for C carriers compared with TT carriers at rs1045642. Of VEN-treated subjects carrying TT genotype at rs1045642, 73.3% remitted compared with 12.5% for CC genotype (odds ratio=6.69; 95% confidence interval=1.72-25.9, P=0.006). These data suggest that antidepressant dose needed to remit can be predicted by an ABCB1 SNP. This has the potential clinical translation implications for dose selection and remission from MDD.
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Affiliation(s)
- A B Singh
- School of Medicine, Deakin University, Geelong, VIC, Australia.
| | - C A Bousman
- Department of Psychiatry, The University of Melbourne, Parkville, VIC, Australia,Department of General Practice, The University of Melbourne, Parkville, VIC, Australia,Swinburne University of Technology, Centre for Human Psychopharmacology, Hawthorne, VIC, Australia,Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia
| | - C H Ng
- Department of Psychiatry, The University of Melbourne, Parkville, VIC, Australia
| | - K Byron
- Healthscope Pathology, Clayton, VIC, Australia
| | - M Berk
- School of Medicine, Deakin University, Geelong, VIC, Australia,Department of Psychiatry, The University of Melbourne, Parkville, VIC, Australia,Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia,Orygen Youth Health Research Centre, Centre for Youth Mental Health, Parkville, VIC, Australia
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Genetic variability and haplotype profile of MDR1 in Saudi Arabian males. Mol Biol Rep 2012; 39:10293-301. [PMID: 23053935 DOI: 10.1007/s11033-012-1906-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Accepted: 09/30/2012] [Indexed: 01/11/2023]
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The single nucleotide polymorphism and haplotype analysis of MDR1 in Jiangsu Han population of China. Biomed Pharmacother 2012; 66:459-63. [PMID: 22902647 DOI: 10.1016/j.biopha.2012.03.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2012] [Accepted: 03/11/2012] [Indexed: 11/22/2022] Open
Abstract
The aim of this study was to perform the frequency distribution of MDR1 gene SNPs and haplotypes of Jiangsu Han population in China. A total of 225 Jiangsu Han unrelated volunteers were enrolled and genotyped by PCR-ASP method at three loci: C1236T (rs1128503), G2677T/A (rs2032582) and C3435T (rs1045642). In total, C and T were found at locus 1236, with the frequency of 35% and 65%, respectively. The most frequent allele at locus 2677 was G with the frequency of 44%, followed by T (41%) and A (15%). At locus 3435, C was more common (60%) than T (40%). The most common haplotype at loci 1236-2677-3435 was T-T-T (31.84%), at loci 1236-2677 was T-T (37.68%), at loci 2677-3435 was G-C (39.06%), and at loci 1236-3435 was T-T (34.28%). The haplotype linkage disequilibrium study found that all three loci were in linkage disequilibrium, such as T-T at loci 1236-2677, T-T at loci 2677-3435 and C-C at loci 1236-3435 (P<0.01). The dendrogram study indicated that the distribution of MDR1 SNPs in Jiangsu Han population were close to Japan and Malay populations and far away from European countries. These findings could shade new lights in population genetics and anthropology studies of Han-Chinese. It also provides basic data for research on MDR1 gene polymorphism, disease association and drug resistance study.
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