肇庆地区人群华法林相关基因CYP2C9*3和VKORC1的多态性分布研究及指导价值

目的 探讨广东省肇庆地区人群华法林相关基因细胞色素P450复合物亚基2C9（CYP2C9）和维生素K环氧还原酶复合物亚基1（VKORC1）多态性分布,并比较性别和中国西双版纳傣族、北京汉族、南方汉族间差异性的分布,为临床医生精准使用华法林进行抗凝治疗提供理论基础。方法 选取2019年5月-2022年1月于肇庆市第一人民医院进行华法林相关基因检测的患者122例,所有患者均采用数字荧光分子杂交技术对CY92C9^*3和VKORC1进行基因多态性检测,比较患者性别间和中国西双版纳傣族、北京地区汉族、南方地区汉族间的基因多态性分布情况,并对比基于药物基因组学指导下的华法林使用剂量与常规剂量使用华法林治疗后2~3 d后国际标准化比值（INR）达标率。结果 122例检测样本中,CY92C9^*3基因位点AA、AC、CC基因型所占的比例分别为95.90%、4.10%、0,C等位基因和T等位基因频率分别为97.95%和2.05%;VKORC1基因位点GG、GA、AA基因型分别为0.82%、19.67%、79.51%,A等位基因和C等位基因频率分别为10.66%和89.34%。不同性别间CY92C9^*3与VKORC1的基因型分布和等位基因分布差异均无统计学意义（P>0.05）。通过已有的数据库进行对比,肇庆地区的CY92C9^*3基因型、等位基因与1000 Genomes Project （1000 GP）西双版纳傣族、北京汉族与南方汉族对比无统计学差异（P>0.05）;但与1000 GP北京汉族对比,VKORC1的基因型和等位基因频率有统计学差异（P<0.05）;与1000GP西双版纳傣族对比,VKORC1的等位基因频率有统计学差异（P<0.05）;华法林在基因组学指导下的剂量与常规剂量治疗后INR达标率差异有统计学意义（P<0.01）。结论 肇庆地区人群存在CY92C9^*3和VKORC1基因多态性,其中VKORC1基因可能存在地域的差异,进行华法林相关基因检测可以为临床制定个体化华法林抗凝方案提供重要的参考价值。     

VKORC1-1639 G/A、CYP2C93*基因多态性对华法林使用剂量的影响

目的 基于VKORC1-1639 G/A及CYP2C93^*的基因多态性初步探讨华法林的使用剂量。方法 收集2016年10月-2018年2月进行华法林用药指导相关基因检测的100例患者,记录患者基本信息（身高、体质量等）。采用数字荧光分子杂交检测VKORC1-1639 G/A,CYP2C93^*的基因型分布,并结合患者年龄、身高、体质量等,根据国际华法林药物基因组学联合会（IWPC）公式计算患者华法林理论剂量。结果 VKORC1-1639 G/A AA、AG、GG基因型实际频率分别为84%,15%,1%;等位基因A,G频率分别为91.5%,8.5%。CYP2C9 3^* AA型、AC型、CC型实际频数分别为91%,9%,0%;等位基因A,C频率分别为95.5%,4.5%。不同VKORC1-1639 G/A、CYP2C93^*基因型华法林理论用量不同,VKORC1-1639 G/A AA型并CYP2C93^* AA型和VKORC1-1639 G/A AG型并CYP2C93^* AA型患者华法林剂量均高于VKORC1-1639 G/A AA型并CYP2C93^* AC型患者;VKORC1-1639 G/A AG型并CYP2C93^* AA型患者华法林用量高于VKORC1-1639 G/A AA型并CYP2C93^* AA型患者,3组间两两比较,差异有统计学意义（P<0.05）。结论 华法林代谢相关基因的基因多态性为VKORC1-1639 G/A AA及CYP2C93^* AA型占多数,表明VKORC1-1639 G/A基因突变率高,CYP2C93^*基因突变率较低,且两者多态性影响个体间华法林的理论剂量。     

基因与临床因素对华法林剂量的影响研究

目的:探讨中国汉族人群相关基因多态性以及患者临床因素对华法林剂量的影响。方法:采用限制性片段长度多态性技术和碱基淬灭探针技术,检测197名心脏机械瓣膜置换术后患者的VKORC1rs9923231、CYP2C9rs1057910以及CYP4F2rs2108622单核苷酸多态性,结合患者临床特征,分析对华法林剂量的影响。结果:VKORC1rs9923231、CYP2C9rs1057910和CYP4F2rs2108622基因多态性及年龄、体质量对华法林剂量的影响在统计学上有显著性差异(P<0.05),并解释了45.2%的华法林剂量差异。结论:中国汉族人群VKORC1rs9923231、CYP2C9rs1057910和CYP4F2rs2108622以及体质量和年龄都是影响华法林剂量的因素。     

VKORC1、CYP2C9、CYP4F2、EPHX1基因多态性对华法林剂量的影响

目的:探讨中国汉族人群VKORC1、CYP2C9、CYP4F2和EPHX1基因多态性对华法林剂量的影响。方法:采用限制性片段多态性技术和碱基淬灭探针技术检测197名心脏机械瓣膜置换术后患者的VKO RC1-1639G>A、CYP2C9 1075A>C、CYP4F2 rs2108622和EPHX1 rs2292566的基因多态性,结合患者的临床特征,分析各因素对华法林剂量的影响。结果:VKO RC1-1639G>A、CYP2C9 1075A>C、CYP4F2 rs2108622、EPHX1 rs2292566基因多态性以及体重和年龄分别解释了30.2%、7.0%、2.8%、3.6%、1.9%和1.7%的华法林个体剂量差异,多因素联合可解释46.7%的华法林个体剂量差异。结论:VKORC1-1639G>A和CYP2C9 1075A>C基因多态性是影响华法林稳定剂量重要的遗传因素;CYP4F2 rs2108622和EPHX1 rs2292566基因多态性以及年龄、体重对华法林的稳定剂量有影响,但较小。     

CYP2C19基因指导冠心病患者经皮冠状动脉介入术后抗血小板药合理应用

目的 探索CYP2C19基因指导冠心病患者经皮冠状动脉介入（PCI）术后抗血小板药物的合理使用。方法 利用医院管理信息系统,收集2015年12月至2016年12月在心内科住院的冠心病患者2 836例,从中选取符合标准的CYP2C19 IM和PM基因型患者480例,根据患者是否根据基因型改变治疗方案,将患者分为常规剂量氯吡格雷组（常规治疗组）、氯吡格雷剂量加倍组和替格瑞洛组,观察各组患者血小板聚集抑制率和1年内主要不良心血管（MACE）及出血事件发生率。结果 最终入选468例患者,替格瑞洛组和剂量加倍组的血小板聚集抑制率均高于常规治疗组（P<0.05）,且替格瑞洛组又明显高于剂量加倍组（P<0.05）。MACE事件发生率方面,各组患者均是再发心肌梗死发生率最高,且替格瑞洛组及剂量加倍组明显低于常规治疗组（P<0.017）,其余MACE各事件及出血发生率各组之间无差异性（P>0.017）。结论 CYP2C19基因指导下冠心病患者PCI术后抗血小板治疗临床效果较好,临床应根据患者基因特点进行个体化合理用药。     

CYP2C9 VKORC1基因多态性指导对非瓣膜性心房颤动患者华法林剂量的影响

目的 探讨CYP2C9、VKORC1基因多态性对非瓣膜性心房颤动（NVAF）患者华法林应用剂量的影响。方法 选择合肥市第二人民医院2017年11月至2019年10月收治的214例NVAF患者,采用随机数字表法分为基因指导组（69例）与对照组（145例）,基因指导组检测VKORC1、CYP2C9基因多态性,对照组按常规剂量给予华法林,比较两组患者华法林起效剂量、有效剂量、起效时间及第14、21天达稳定剂量患者比例等指标。结果 基因指导组患者在华法林应用初始剂量为（1.67±1.63）mg、稳定剂量为（2.02±0.94）mg,均低于对照组,起效时间为（7.62±2.87）d,短于对照组短,差异有统计学意义（P<0.05）。CYP2C9、VKORC1组华法林应用初始剂量、稳定剂量均低于对照组,起效时间短于对照组,差异有统计学意义（P<0.05）。基因指导组第14、21天达稳定剂量患者比例（76.44%、98.27%）高于对照组,差异有统计学意义（P<0.05）。结论 VKORC1、CYP2C9基因多态性检测结合NVAF患者临床特点可为临床精准合理应用华法林提供参考。     

细胞色素P450酶2C9和维生素K环氧化物还原酶复合体1基因多态性对瓣膜置换术后华法林剂量影响分析

目的 分析细胞色素P450酶2C9（CYP2C9）和维生素K环氧化物还原酶复合体1（VKORC1）基因多态性对瓣膜置换术后华法林剂量的影响。方法 选取自2015年3月—2017年12月期间于漯河市中心医院行瓣膜置换术后口服华法林的127例患者为研究对象。采用PCR-RFLP法分别检测其CYP2C9和VKORC1基因型,同时记录患者的华法林日均服用剂量、血浆总浓度及游离浓度。对不同基因型及临床特征与华法林日常服用剂量进行直线相关及多元回归分析。结果 华法林日均服用剂量对比,CYP2C9（1061A/C）基因型AA患者显著高于基因型AC患者（P<0.05）,VKORC1（1639 G/A）基因型AA患者显著低于基因型AG患者（P<0.05）,VKORC1（1173 C/T）基因型TT患者显著低于基因型CT患者（P<0.05）。华法林血浆总浓度及游离浓度对比, VKORC1 （1639 G/A）基因型AA患者显著低于基因型AG患者（P<0.05）,VKORC1（1173 C/T）基因型TT患者显著低于基因型CT患者（P<0.05）。女性患者的华法林日均服用剂量显著低于男性患者（P<0.05）,≥70岁和60～69岁患者显著低于60岁以下各年龄段（P<0.05）。直线相关分析及多元回归分析结果提示,华法日均服用剂量与CYP2C9、VKORC1基因型和年龄、性别相关（P<0.05）。结论 CYP2C9和VKORC1基因多态性与瓣膜置换术后华法林日常服用剂量个体化相关,同时年龄和性别也是影响因素之一。     

CYP2C19基因多态性对PCI术后患者氯吡格雷血药浓度、血小板抑制率和安全性的影响

目的 探讨CYP2C19基因多态性对氯吡格雷血药浓度、血小板抑制率和安全性的影响。方法 根据纳入和排除标准,筛选我院使用氯吡格雷的经皮冠状动脉介入治疗(PCI)术后患者,收集氯吡格雷用药后第6天的血样,采用反相高效液相色谱(RP-HPLC)法测定氯吡格雷血药浓度,非扩增免疫杂交技术检测患者CYP2C19基因型,并通过血栓弹力图来评估血小板抑制率。应用SPSS 20.0对数据进行统计分析。结果 共纳入87例患者,男性46例,女性41例;其中34例为快代谢型,38例中代谢型,15例慢代谢型;结果显示,快、中代谢型的药物浓度无显著性差异（P=0.667）,而慢代谢型与快、中代谢型药物浓度有显著性差异(P<0.05);方差分析和卡方检验显示CYP2C19基因多态性对氯吡格雷的血小板抑制率和安全性的影响有显著性差异(P<0.05）。结论 仅根据CYP2C19基因型指导氯吡格雷临床用药并不一定达到较好的治疗效果,可联合CYP2C19基因型检测与血药浓度监测来指导氯吡格雷的临床个体化给药。     

CYP2C9、VKORC1基因多态性对华法令抗凝治疗维持剂量的影响

目的：研究细胞色素P4502C9基因（CYP2C9）和维生素K环氧化物还原酶复合物1基因（VKORC1）在华法令抗凝治疗患者的多态性分布,并探讨其对抗凝剂量的影响。方法：收集74例服用华法令抗凝治疗病人的外周血,测定其凝血酶原时间国际标准化比值（INR）和CYP2C9、VKORC1基因类型,探讨基因多态性的分布特点,以及华法令维持剂量与基因多态性的关系。结果：CYP2C9基因分布主要为野生型,突变型较少,抗凝治疗的维持剂量野生型组与突变组无明显差别。 VKORC1基因型的分布AA型为主,AG型较少,GG型未见,抗凝治疗的维持剂量AG组明显高于AA组。结论：CYP2C9、VKORC1基因在中国汉族人群中具有遗传多态性, VKORC1基因的多态性在华法令抗凝治疗中具有显著意义。     

肾移植患者SLCO1B3基因多态性与他克莫司血药浓度相关性研究

目的 探究肾移植患者SLCO1B3基因多态性与术后早期他克莫司血药浓度的相关性。方法 选取昆明市第一人民医院68例肾移植患者为研究对象,运用化学免疫发光法监测他克莫司血药浓度,同时采用聚合酶链反应法检测CYP3A5^*3、SLCO1B3 T334G和G699A基因多态性,并进行基因分型,分析各基因型与他克莫司血药浓度的相关性。结果 CYP3A5^*3不同基因型对术后他克莫司血药浓度和标准化血药浓度有影响,差异具有统计学意义(P＜0.05),SLCO1B3 T334G和G699A基因位点不同基因型对术后他克莫司血药浓度和标准化血药浓度无影响,差异均无统计学意义。结论 与CYP3A5^*3/^*3基因型相比,CYP3A5^*1等位基因携带者达到相同的他克莫司浓度需要增加他克莫司给药剂量。SLCO1B3 T334G和G699A基因多态性对肾移植术后早期他克莫司血药浓度无影响。     

CYP4F2 rs2108622: a minor significant genetic factor of warfarin dose in Han Chinese patients with mechanical heart valve replacement

AIMS

The objective of this study was to assess the effect of the CYP4F2 on the daily stable warfarin dose requirement in Han Chinese patients with mechanical heart valve replacement (MHVR).

METHODS

From March 2007 to November 2008, 222 Han Chinese MHVR patients were recruited in our study. VKORC1 3673G>A, 5417G>T, CYP2C9*3 and CYP4F2 rs2108622 were genotyped by using the polymerase chain reaction restriction fragment length polymorphism method (PCR-RFLP). Polymorphisms of VKORC1 9041G>A were detected by direct sequencing. Multiple linear regression analysis was used to investigate the contribution of CYP4F2.

RESULTS

The CYP4F2 rs2108622 CT/TT group took a significantly higher stable warfarin dose (3.2 mg day⁻¹) than the CC group (2.9 mg day⁻¹, 95% CI 0.2, 1.0, P= 0.033). The multiple linear regression model included VKORC1 3673G>A, CYP2C9, CYP4F2 genotypes and clinical characteristics. The model could explain 56.1% of the variance in stable warfarin dose in Han Chinese patients with MHVR. CYP4F2 contributed about 4% to the variance in the warfarin dose. There was no variation in the SNPs of VKORC1 5417G>T.

CONCLUSION

CYP4F2 is a minor significant factor of individual variability in the stable warfarin dose in Han Chinese patients with MHVR. The effect of CYP2C9 and VKORC1 genotypes on variability in the stable warfarin dose had also been confirmed.     

Effect of CYP2C9, VKORC1, CYP4F2 and GGCX genetic variants on warfarin maintenance dose and explicating a new pharmacogenetic algorithm in South Indian population

Objective

To determine the influence of genetic polymorphisms on warfarin maintenance dose and to explicate an algorithm using the pharmacogenetic and clinical factors to determine the maintenance and/or starting dose of warfarin in South Indian patients receiving warfarin therapy.

Methods

Patients receiving stabilized warfarin therapy (n?=?257) were included in the study. Single nucleotide polymorphisms (SNPs) of CYP2C9 (rs1799853 and rs1057910), VKORC1 (rs9923231, rs7196161, rs2884737, rs9934438, rs8050894, rs2359612 and rs7294), CYP4F2 (rs2108622) and GGCX (rs11676382) were genotyped by the quantitative real time-PCR method.

Results

The mean daily maintenance dose of warfarin was found to be 4.7?±?2.1 mg/day. Patients with the CYP2C9*1/*2, *1/*3 and *2/*3 variant genotypes required a 51.0 (2.8 mg), 60.9 (2.3 mg) and 62.2 % (2.2 mg) lower daily maintenance dose of warfarin, respectively, than those patients with the CYP2C9*1/*1 wild-type genotype (5.2 mg) (p?<?0.0001). The genetic variants of CYP2C9, VKORC1 and GGCX were associated with decreased warfarin dose, except for rs7196161, rs7294 and rs2108622 which were associated with an increased warfarin dose. Genetic variations of CYP2C9 (*2 and *3), VKORC1 (rs9923231, rs7294, rs9934438 and rs2359612), CYP4F2, GGCX and non-genetic factors such as age, body weight, clinical status (post mechanical valve replacement) could explain up to 62.1 % of the overall variation (adjusted r ² 60.2 %, p?<?0.0001) in warfarin maintenance dose.

Conclusion

Genetic polymorphisms of CYP2C9, VKORC1, CYP4F2 and GGCX are important predictive factors of warfarin maintenance dose, and the developed algorithm will be useful to predict the required maintenance and/or starting warfarin dose in South Indian populations.     

Impact of Genetic Factors (CYP2C9, VKORC1 and CYP4F2) on Warfarin Dose Requirement in the Turkish Population

Warfarin has a narrow therapeutic index and displays marked person‐to‐person variation in dose requirement. Functional polymorphisms at candidate genes can therefore offer utility as biomarkers to individualize warfarin treatment. The main objective of this study was to determine whether and to what extent variability in warfarin dose requirements was determined by polymorphisms in CYP2C9, VKORC1, CYP4F2 (rs2108622) and EPHX1 (rs2292566) in the Turkish population. Patients (n = 107) who had stable doses and international normalized ratio (INRs) at their last three consecutive visits were registered. Their demographic factors, concurrent medications, warfarin‐related bleedings or thromboembolisms, smoking, alcohol intake and weekly green vegetable consumption were recorded. From a blood sample, DNA was isolated and genotyped by real‐time PCR for polymorphisms of CYP2C9, VKORC1, CYP4F2 and EPHX1. A regression analysis was used to determine the independent effects of genetic and non‐genetic factors on warfarin dose optimization. In our study, in addition to age, genetic variants of CYP2C9, VKORC1 and CYP4F2 were found to be significant predictor variables for the maintenance dose for warfarin, explaining 39.3% of dose variability. VKORC1 and CYP2C9 genotypes remain predictor variables of the warfarin dose, and we first found that CYP4F2 (rs2108622) contributes to dose variability in the Turkish population as well. These observations may be of benefit to future translation research with a view to global personalized medicine in regions hitherto understudied such as the Turkish population so as to rationalize initial warfarin dose and reduce the burden of frequent INR measurements.     

Pharmacogenomics of warfarin in populations of African descent

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.     

Exploring warfarin pharmacogenomics with the extreme-discordant-phenotype methodology: impact of <Emphasis Type="Italic">FVII</Emphasis> polymorphisms on stable anticoagulation with warfarin

Purpose  To explore the pharmacogenomics of warfarin using the extreme-discordant-phenotype (EDP) methodology. Methods  The target phenotype was the stable warfarin dose prescribed to 353 patients. Pharmacogenetic polymorphisms assessed were coagulation factor VII (FVII) -401G>T and FVII -402G>A, VKORC1 3673G>A, and CYP2C9*2, *3, *5, and *11 alleles. The EDP analyses contrasted the frequencies of these polymorphisms at different cutoff points (5th through 30th percentiles of the warfarin dose distribution) at opposite ends of the warfarin dose distribution. Results  Significant differences existed in FVII -402G>A genotype frequency at the 5th percentile with an over-representation of the wildtype GG genotype at low warfarin doses and in VKORC1 3673G>A and CYP2C9 polymorphisms at all cutoff points where the variant alleles were overrepresented at low warfarin doses. Conclusion  The EDP methodology provides increased statistical power for detection of small contributions of genetic polymorphisms to multiplex drug-response phenotypes, such as warfarin dose requirement for adequate anticoagulation.