2.Influence of genetic polymorphisms and non-genetic factors on the maintenance dose of warfarin.
Jianglong HOU ; Xin DONG ; Yuqing WANG ; Gang WANG ; Li DONG ; Jesse LI-LING
Chinese Journal of Medical Genetics 2015;32(5):629-634
OBJECTIVE To assess the influence of genetic polymorphisms and non-genetic factors on warfarin maintenance dose variations in order to provide guidance for personalized use of warfarin. METHODS Two hundred patients from outpatient and inpatient with stable international normalized ratio(INR) were recruited. Clinical data and blood samples were collected. Genotypes of 4 genes involved in warfarin metabolic pathways were determined with Sanger sequencing. Based on statistical analysis of warfarin maintenance dosage, a mathematical model was established. RESULTS Among non-genetic factors, the age and height have significant influence in warfarin dosage. The dosage is negatively correlated with age but positively correlated with height. The difference in dosage for between the 20-year-old group and 60-year-old group has reached 1.81 mg/day, and that for between the 140 cm in height and 180 cm in height groups has reached 1.06 mg/day. VKORC1 -1639G/A, CYP2C9 430C/T, CYP2C9 1075A/C and CYP4F2 V433M polymorphisms have significant influence on stable warfarin dosage. The dosage for patients with wild type and mutant genotypes has varied from 0.35 mg/day to 0.84 mg/day. CONCLUSION Non-genetic factors and genetic polymorphisms play important roles in personalized variations of warfarin maintenance dose. The establishment of mathematical models considering multiple factors is helpful in evaluating the safety and effectiveness of warfarin dosage.
Adult
;
Aged
;
Anticoagulants
;
administration & dosage
;
Cytochrome P-450 CYP2C9
;
genetics
;
Cytochrome P-450 Enzyme System
;
genetics
;
Cytochrome P450 Family 4
;
Female
;
Humans
;
Male
;
Middle Aged
;
Polymorphism, Genetic
;
Vitamin K Epoxide Reductases
;
genetics
;
Warfarin
;
administration & dosage
3.Population pharmacokinetic/pharmacodynamic modeling of warfarin by nonlinear mixed effects model.
Rong-fang LIN ; Wei-wei LIN ; Chang-lian WANG ; Pin-fang HUANG ; Su-jun FANG
Acta Pharmaceutica Sinica 2015;50(10):1280-1284
The study aimed to establish a population pharmacokinetic/pharmacodynamic (PPK/PD) model of warfarin. PCR-RFLP technique was used to genotype the CYP2C9 and VKORC1 polymorphisms of 73 patients. RP-HPLC-UV method was used to determine the 190 plasma concentrations of warfarin. Application of NONMEM, the clinical information and 263 international normalized ratio (INR) monitoring data were used to investigate the effect of genetic, physiological, pathological factors, other medication on clearance and anticoagulant response. The final model of warfarin PPK/PD was described as follows: CL = θCL · (WT/60)θWT · θCYP · eηCL (if CYP2C9*1/*1, θCYP = 1; if *1/*3, θCYP = 0.708); EC50 = θEC50 · θVKOR · eηEC50 (if VKORC1- 1639AA, θVKOR = 1; if GA, θVKOR = 2.01; V = θV; K(E0) = θK(E0); Emax = θEmax; E0 = θE0 · eηE0. Among them, the body weight (WT), CYP2C9 and VKORC1 genotype had conspicuous effect on warfarin PK/PD parameters. The goodness diagnosis, Bootstrap, NPDE verification showed that the final model was stable, effective and predictable. It may provide a reference for opitimizing the dose regimen of warfarin.
Anticoagulants
;
pharmacology
;
Body Weight
;
Cytochrome P-450 CYP2C9
;
genetics
;
Genotype
;
Humans
;
International Normalized Ratio
;
Nonlinear Dynamics
;
Polymorphism, Genetic
;
Vitamin K Epoxide Reductases
;
genetics
;
Warfarin
;
pharmacokinetics
5.Verification of accuracy of warfarin stable dose prediction models in Shandong population.
Yiping GE ; Fengxia QU ; Songtao WANG ; Xiao GUO ; Cuicui WANG ; Shiyun LIU ; Aiqing MA ; Xianyan JIANG ; Kai TAN
Chinese Journal of Medical Genetics 2020;37(4):401-404
OBJECTIVE:
To compare the accuracy of five warfarin-dosing algorithms and warfarin stable dose model (2.5 mg/day) for Shandong population.
METHODS:
One hundred and twenty five patients who achieved stable warfarin dose were enrolled. Clinical and genetic data were used to evaluate the value of each algorithm by calculating the percentage of patients whose predicted warfarin dose was within 20% of the actual stable therapeutic dose and mean absolute error (MAE).
RESULTS:
The frequency of patients with CYP2C9*1/*1, CYP2C9*1/*3 and CYP2C9*1/*2 genotype was 92.00%, 7.20%, 0.80%, respectively. That of VKORC1-1639 AA, AG and GG genotype was 82.40%, 15.20%, 2.40%, respectively. CYP4F2*1/*1, *1/*3, *3/*3 genotype was 50.40%, 39.20%, 10.40%, respectively. With the same genotypes for other loci, patients who carried at least one VKORC1-16398G mutant allele had increased warfarin stable daily dose compared with VKORC1-1639AA. Compared with CYP4F2*1/*1, those carrying at least one CYP4F2*3 mutant allele had warfarin stable daily dose increased by 5.9%-13.00%. The percentage of ideal prediction calculated from IWPC model (59.20%), Huang model (57.60%) and Ohno model (52.80%) were higher than others. The MAE were 0.35 (95%CI: 0.11-0.49), 0.15 (95%CI: 0.10-0.32), 0.39 (95%CI: 0.12-0.51), respectively.
CONCLUSION
The polymorphisms of CYP2C9, VKORC1 and CYP4F2 genes can influence the stable dose of warfarin in Shandong population. IWPC algorithm is suitable for guiding the use of warfarin in this population.
Anticoagulants
;
administration & dosage
;
Aryl Hydrocarbon Hydroxylases
;
Cytochrome P-450 CYP2C9
;
genetics
;
Cytochrome P450 Family 4
;
genetics
;
Dose-Response Relationship, Drug
;
Genotype
;
Humans
;
Models, Theoretical
;
Polymorphism, Genetic
;
Vitamin K Epoxide Reductases
;
genetics
;
Warfarin
;
administration & dosage
6.Influence of warfarin related genes and non- genetic factors on administrative dose in Shanghai area.
Wenfang ZHUANG ; Depei WU ; Zhaoyue WANG
Chinese Journal of Hematology 2014;35(1):13-17
<b>OBJECTIVEb>To investigate the distribution of Warfarin related genes and the relationship between genotype, gender, weight, age and the administrative dose of Warfarin in Shanghai area.
<b>METHODSb>The clinical data (including sex, age and administrative dose of Warfarin) of 214 patients with stable warfarin dose and the international normalized ratio (INR) between 1.5-3.0 were collected. Polymerase chain reaction-high resolution melting (PCR-HRM) technique was used to detect the single nucleotide polymorphisms (SNPs) of CYP2C9*2 rs1799853, CYP2C9*3 rs1057910, CYP4F2 rs2108622 and VKORC1 rs9934438. The associations of genotype data with clinical material, including gender, age, weight and warfarin dosage were analyzed.
<b>RESULTSb>Among 214 patients, 99.53% (213 cases) patients with CC (wild type) of CYP2C9*2 rs1799853 and only 1 case with CT (heterozygous mutation) ; 92.52% (198 cases) with AA (wild type), 7.48% (16 cases) with CA (heterozygous mutation) of CYP2C9*3rs1057910; about 57.94% (124 cases) with CC(wild type) of CYP4F2 rs2108622, the CT and TT (heterozygous and homozygotic mutation) accounted for 42.06% (90 cases). In SNP VKORC1 rs9934438, 82.71% (177cases) were TT (wild type), 17.29% (37 cases) CT (heterozygous mutation). There are no significant difference (P=0.0872) in patients with maintenance dose in CYP2C9*3 between AA and CA gene mutations[(2.816±1.055) mg/d vs (2.352±0.805)mg/d], and no significant difference (P=0.5954) of that in CYP4F2 between CC and CT+TT gene mutations [(2.736±1.062) mg/d vs (2.813±1.034) mg/d]; but the significant differences (P=0.0001) does exist in patients with maintenance dose in VKORC1 between TT and CT variants [(2.597±0.866) mg/d vs (3.660±1.350) mg/d]. The warfarin maintain dosage was negatively correlated with the average age (r=-0.9669) and positively correlated with the body weight (r=0.9022).
<b>CONCLUSIONb>It is of great significance to detect the VKORC1 variants for warfarin dosage adjustment in Shanghai population. However, the detection of CYP2C9*2 and CYP4F2 polymorphisms had no significant associations for warfarin dosage adjustment.
Adult ; Aged ; Aged, 80 and over ; Anticoagulants ; administration & dosage ; Body Weight ; China ; epidemiology ; Cytochrome P-450 CYP2C9 ; genetics ; Cytochrome P-450 Enzyme System ; genetics ; Cytochrome P450 Family 4 ; Dose-Response Relationship, Drug ; Female ; Genotype ; Heterozygote ; Humans ; International Normalized Ratio ; Male ; Middle Aged ; Sex Distribution ; Vitamin K Epoxide Reductases ; genetics ; Warfarin ; administration & dosage ; Young Adult
7.Extremely low warfarin dose in patients with genotypes of CYP2C9*3/*3 and VKORC1-1639A/A.
Lei GAO ; Lei HE ; Jin LUO ; Bin XU ; Jie YANG ; Yu-xiao ZHANG ; Ting YANG ; Ke LI ; Jin-wen TIAN ; Hong-juan WANG ; Yu-sheng ZHAO ; Cai-yi LU ; Wen-zi ZHANG ; Tong YIN
Chinese Medical Journal 2011;124(17):2767-2770
<b>BACKGROUNDb>Patients with the genotypes of both CYP2C9*3/*3 and VKORC1-1639 A/A are expected to require the lowest dose of warfarin, and to have a greatly increased risk of bleeding. The experience for the dosing of warfarin in such extremely rare cases has been seldom reported.
<b>METHODSb>Demographic and clinical data from two cases with stable low dose of warfarin in China were studied by resequencing the corresponding gene segments in their whole blood DNA. The potential clinical value of the pharmacogenetic algorithm for them was evaluated by calculating the stable dose of warfarin in pharmacogenetic algorithm developed by International Warfarin Pharmacogenetics Consortium.
<b>RESULTSb>Both cases (68-year-old female and 50-year-old male) were diagnosed as chronic nonvalvular atrial fibrillation needing warfarin treatment, with target international normalized ratio (INR) 2 to 3. Case 1 had stable warfarin dose of 0.625 mg/d and case 2 1.25 mg/d. They needed more than 1 month to stabilize their anticoagulation. Exceeding INR values were recorded for them when the dose of warfarin was no more than 2 mg/d. Hemorrhagic complication appeared in case 1 when the dose was titrated from 2.5 to 1.25 mg/d. No concomitant medicine to increase or decrease the INR value was recorded for them. Genotyping CYP2C9 and VKORC1 showed both patients were the carriers of the homozygous alleles -CYP2C9*3/*3 and VKORC1-1639 A/A. Their stable doses of warfarin calculated by the pharmacogenetic dose algorithm (0.672 mg/d for case 1 and 1.16 mg/d for case 2) were comparable with their actual stable therapeutic doses.
<b>CONCLUSIONSb>Two Chinese with the rare genotypes of both CYP2C9*3/*3 and VKORC1-1639 A/A were found to require the extremely low dose of warfarin. The pharmacogenetic algorithm incorporating the variances of VKORC1 and CYP2C9 genotypes, as well as the non-genetic factors could predict their stable dose of warfarin with high accuracy.
Aged ; Anticoagulants ; adverse effects ; Aryl Hydrocarbon Hydroxylases ; genetics ; Cytochrome P-450 CYP2C9 ; Female ; Genotype ; Hemorrhage ; chemically induced ; Humans ; Male ; Middle Aged ; Mixed Function Oxygenases ; genetics ; Pharmacogenetics ; Vitamin K Epoxide Reductases ; Warfarin ; adverse effects
8.Match of functional module with chassis in 7-dehydrocholesterol synthesis.
Ying ZHANG ; Lu ZHANG ; Duo LIU ; Mingzhu DING ; Xiao ZHOU ; Yingjin YUAN
Chinese Journal of Biotechnology 2014;30(1):30-42
The key challenge to generate engineered cells by synthetic biology for producing 7-dehydrocholesterol (7-DHC) in a high titer is the match between functional module and chassis. Our study focused on solving this problem by combining different promoters and yeast chassis to increase 7-DHC production. To optimize the chassis in order to accumulate zymosterol, the substrate for 7-DHC synthesis, we overexpressed truncated HMG-CoA reductase (tHmglp) and squalene epoxidase (Erglp), both are key genes of yeast endogenous zymosterol biosynthetic pathway. In addition, we knocked out C-24 methyl transferase (Erg6p) and C-22 dehydrogenase (Erg5p) to inhibit the conversion of zymosterol to ergosterol. By introducing heterologous C-24 reductase under three promoters with different strengths, namely TDH3p, PGK1p and TDH1p, we constructed functional modules of diverse activities. Nine engineeredcells were generated based on the combination of these three modules and three chassis. The result shows that the engineered cell composed of functional module regulated by TDH3p and chassis SyBE_000956 had the highest 7-DHC production, indicating a better match than others. This study provides evidences for importance of match and empirical support for rational design of subsequent researches.
Cholesterol
;
metabolism
;
Cytochrome P-450 Enzyme System
;
genetics
;
Dehydrocholesterols
;
metabolism
;
Gene Knockout Techniques
;
Hydroxymethylglutaryl CoA Reductases
;
metabolism
;
Industrial Microbiology
;
Methyltransferases
;
genetics
;
Promoter Regions, Genetic
;
Saccharomyces cerevisiae
;
genetics
;
metabolism
;
Saccharomyces cerevisiae Proteins
;
genetics
;
Synthetic Biology
9.Impact of six genetic polymorphisms on Warfarin maintenance dose variation in Chinese Han population.
Ying LOU ; Lulu HAN ; Yan LI ; Xiaoxing ZHANG ; Zhihong LIU ; Min TANG ; Haiwen YU ; Wei WANG ; Jianping XU ; Hong LIU ; Yishi LI
Chinese Journal of Medical Genetics 2014;31(3):367-371
<b>OBJECTIVEb>To evaluate the effect of VKORC1, CYP2C9, GGCX, PROC, EPHX1 and CYP4F2 gene polymorphisms on Warfarin maintenance dose variation in Chinese Han Population.
<b>METHODSb>Four hundred eighty-eight patients with prosthetic heart valves, atrial fibrillation or pulmonary thromboembolism and achieved stable Warfarin dose were enrolled. TaqMan probe or direct sequencing were used to genotype Y9VKORC1, CYP2C9, GGCX, EPHX1 and CYP4F2 gene polymorphisms. Demographic characteristics, stable therapeutic dose of Warfarin and concomitant medications were collected for all patients. The effect of VKORC1, CYP2C9, GGCX, PROC, EPHX1 and CYP4F2 gene polymorphisms, demographic characteristics and concomitant medications on Warfarin daily maintenance dose were analyzed with statistical method.
<b>RESULTSb>VKORC1 and CYP2C9 gene polymorphisms could explain more than 50% Warfarin maintenance dose variation in recruited patients, while CYP4F2 gene polymorphisms could only explain 1%. GGCX, PROC and EPHX1 gene polymorphisms had no impact no Warfarin maintenance dose. VKORC1 and CYP2C9 gene polymorphisms have a greater impact on Warfarin maintenance dose compared with demographic characteristics and concomitant medications.
<b>CONCLUSIONb>VKORC1 and CYP2C9 gene polymorphisms have a significant impact on Warfarin maintenance dose in Chinese Han population.
Adult ; Aged ; Aryl Hydrocarbon Hydroxylases ; genetics ; Asian Continental Ancestry Group ; ethnology ; genetics ; Atrial Fibrillation ; drug therapy ; ethnology ; genetics ; Cytochrome P-450 CYP2C9 ; Cytochrome P-450 Enzyme System ; genetics ; Cytochrome P450 Family 4 ; Dose-Response Relationship, Drug ; Epoxide Hydrolases ; genetics ; Female ; Humans ; Male ; Middle Aged ; Polymorphism, Single Nucleotide ; Protein C ; genetics ; Pulmonary Embolism ; drug therapy ; ethnology ; genetics ; Treatment Outcome ; Vitamin K Epoxide Reductases ; genetics ; Warfarin ; administration & dosage ; Young Adult
10.Impact of five genetic polymorphisms on inter-individual variation in warfarin maintenance dose.
Sheng-wen HUANG ; Dao-kang XIANG ; Hai-li WU ; Bao-lin CHEN ; Bang-quan AN ; Gui-fang LI
Chinese Journal of Medical Genetics 2011;28(6):661-665
<b>OBJECTIVEb>To investigate the effect of genetic polymorphisms in VKORC1, CYP2C9, GGCX, EPHX1, APOE genes on inter-individual variation in warfarin maintenance dose.
<b>METHODSb>Two hundred and forty-nine patients with stable warfarin dose were enrolled in this study, and the clinical data and blood samples of the patients were collected. Genotypes for the 5 genes were determined by using PCR and denaturing high performance liquid chromatography (DHPLC) assay. The warfarin maintenance doses were compared among patients with different genotypes of the 5 genes, and a warfarin stable dosing algorithm was derived based on genetic and non-genetic factors.
<b>RESULTSb>Of the 5 genes, VKORC1, CYP2C9 and GGCX were associated with warfarin stable dose. The multiple linear regression analysis indicated that VKORC1, CYP2C9 and GGCX genes, age and weight, had significant influence on inter-individual variation in warfarin stable dose, which contributed 30.2%, 22.8%, 1.5%, 4.7% and 6.7% respectively. The warfarin stable dosing algorithm acquired from the optimal regression model could explain 57.8% variation in warfarin dose.
<b>CONCLUSIONb>This study suggested that genetic factors are the major determinants of the warfarin maintenance dose, and warfarin stable dosing algorithm may be useful for helping clinicians to prescribe warfarin with greater safety and efficiency.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Alleles ; Anticoagulants ; administration & dosage ; Apolipoproteins E ; genetics ; Aryl Hydrocarbon Hydroxylases ; genetics ; Carbon-Carbon Ligases ; genetics ; Cytochrome P-450 CYP2C9 ; Epoxide Hydrolases ; genetics ; Female ; Gene Frequency ; Genotype ; Humans ; Male ; Middle Aged ; Mixed Function Oxygenases ; genetics ; Pharmacogenetics ; Polymorphism, Single Nucleotide ; Precision Medicine ; Vitamin K Epoxide Reductases ; Warfarin ; administration & dosage ; Young Adult