荧光多聚酶链反应测定细胞色素P450 3A5 1*3多态性

目的：建立荧光多聚酶链反应测定细胞色素P450 3A5 1＊3的多态性。方法：以TaqMan技术为基础,采用等位基因特异性引物,在引物的3′端第二位人为引入一个非配对碱基提高引物的分辨力。对PCR反应的Mg^2＋和探针浓度进行优化,同时对本方法的灵敏度和精密度进行了研究,应用直接DNA测序法对准确度进行评价。结果：优化后的Mg^2＋和探针浓度分别为3．5mmol／L和0．7μmol／L,批内（n=20）CV为1．41％,批间（n=20）CV为1．72％,在25μl反应体系中,样本DNA浓度5．0×10^2～5．0×10^6Pg范围内可获满意结果。本法确定的50份标本基因型与直接DNA测序法结果完全一致。结论：本法快速、灵敏、可靠,适用于细胞色素P450 3A5 1＊3多态性测定。     

CYP3A4基因多态性与临床疾病易感性的研究进展

细胞色素P450 3A4(CYP3A4)作为人体内代谢药物的主要酶细胞色素P450超家族中的重要成员,参与多种内、外源性化学物质在人体内的转化代谢的过程,而其基因多态性也与多种临床疾病的易感性密切相关。本文就CYP3A4基因多态性与临床多种疾病的易感性作一综述。     

等位基因特异性PCR检测CYP3A5和MDR-1基因多态性方法的建立及临床应用

目的用等位基因特异性PCR(ARMS-PCR)检测细胞色素P450酶CYP3A5(A6986G)和多药耐药基因MDR-1(C3435T)基因多态性,探讨其与肾移植受者他克莫司(Tac)血药浓度和剂量比的相关性。方法根据CYP3A5(A6986G)和MDR-1(C3435T)基因多态性位点分别设计ARMS-PCR引物,分析72例肾移植受者外周血基因组DNA中该2个基因位点的多态性,同时以DNA测序法为金标准进行验证。化学发光微粒子免疫分析法测定肾移植受者血Tac浓度,并比较术后1个月时不同基因型受者之间血Tac浓度、Tac剂量/Tac用量的差异。结果建立的ARMS-PCR法与DNA测序法检测符合率为100%。72例肾移植受者中,CYP3A5*1/*1、*1/*3和*3/*3基因型的发生频率分别为18.1%、31.9%和50.0%,MDR-1 C/C、C/T和T/T基因型的发生频率分别为27.8%、58.3%和13.9%。此外,不同CYP3A5基因型肾移植受者的血Tac浓度(P=0.014)和Tac浓度/Tac用量(P=0.019)均存在明显差异,进一步两两比较发现,CYP3A5*3/*3基因型受者血Tac浓度/Tac用量明显高于*1/*1和*1/*3基因型(P均0.05)。结论成功建立检测CYP3A5和MDR-1基因多态性的ARMS-PCR法,肾移植受者CYP3A5*3基因多态性与Tac的药代动力学明显相关。     

壮族与汉族原发性高血压患者ACE及CYP3A5基因多态性的关系分析

目的 探讨壮族人群和汉族人群原发性高血压与血管紧张素转化酶(ACE)及细胞色素P450 3A5(CYP3A5)基因分布频率的关系,并将两个民族原发性高血压人群的ACE及CYP3A5基因分布频率进行对比,为精准治疗原发性高血压提供新的临床依据。方法 选取400例原发性高血压患者(壮族病例组200例,汉族病例组200例)为研究对象,采用实时荧光定量聚合酶链反应对ACE基因及CYP3A5基因的多态性进行检测。结果 壮族病例组与汉族病例组中ACE及CYP3A5基因型频率及等位基因分布频率比较,差异均无统计学意义(P>0.05)。壮族病例组中不同性别间ACE及CYP3A5的基因型频率及等位基因分布频率比较,差异均无统计学意义(P>0.05)。汉族病例组中不同性别之间ACE的基因型频率及等位基因分布频率比较,差异有统计学意义(P<0.01),CYP3A5的基因型频率及等位基因分布频率比较,差异均无统计学意义(P>0.05)。相同性别不同民族之间ACE及CYP3A5的基因型频率及等位基因分布频率比较,差异均无统计学意义(P>0.05)。结论 壮族与汉族原发性高血压患者A...     

CYP1A2基因单核苷酸多态性与前列腺增生术后尿路感染风险的关系

目的 探讨细胞色素P450酶1A2(CYP1A2)单核苷酸多态性(SNP)与前列腺增生术后尿路感染易感性的关系.方法 将2017年1月至2020年12月于该院就诊和治疗的行经尿道前列腺等离子双极电切术(TUPKRP)的前列腺增生患者82例纳入研究,根据是否发生尿路感染分为感染组(n=19)和非感染组(n=63).提取2...     

基于Taqman荧光ARMS-PCR技术检测CYP3A5基因多态性方法的建立

目的建立一种基于Taqman荧光的ARMS-PCR技术检测人外周全血样本CYP3A5*3(rs776746)基因多态性的新方法。方法根据CYP3A5和内参基因的保守序列分别设计特异性引物及探针,建立CYP3A5*1和CYP3A5*3 Taqman荧光ARMS-PCR检测体系及其测序体系,并对200例人外周全血样本进行检测及金标准测序对比验证,分析2种检测方法的一致性,并统计分析CYP3A5*3基因多态性的分布。结果该方法可检测人外周全血样本CYP3A5*3(rs776746)基因多态性,其检测结果与sanger测序一致性为100%。200例外周血样本CYP3A5*3基因型分布:*1/*1型19例(9.5%),*1/*3型为62例(31.0%),*3/*3型为119例(59.5%)。结论本研究建立的基于Taqman荧光ARMS-PCR技术的检测方法能够简单、快速、准确地检测CYP3A5*3基因型,适用于临床推广。     

CYP3A5基因遗传多态性及临床研究进展

细胞色素酶P4503A（cytochrome P4503A,CYP3A）是人体代谢许多内源性化合物、外源性底物及其前致癌物的一类重要的肝脏药物氧化代谢酶,占成人肝脏细胞色素总量的30％,代谢超过50％的临床用药物。而CYP3A5是P4503A家族中活性最强的酶之一,因存在突变多态性,不同的单核苷酸多态（single nueleotide polyrnorphism,SNP）可导致药物有不同的代谢活性,对不同SNP的分析可以对个性化用药做出指导。不同的SNP可能还与某些疾病的遗传易感性相关,就上述CYP3A5的遗传多态性及临床意义进行综述。     

高分辨熔解曲线分析CYP3A5基因多态性方法学的建立

目的通过建立一种较为简单灵敏的高分辨熔解曲线(HRM)方法,对CYP3A5单核苷酸多态性(SNP)位点进行测定,从而确定CYP3A5基因型,用于指导临床他克莫司的用药剂量。方法根据CYP3A5SNP位点基因组序列设计引物,利用HRM方法检测已知基因型标本,选取最佳引物,并通过同测序结果比对的方式确定该方法检测CYP3A5基因型的正确度、重复性以及灵敏度。结果利用该方法可以直接判断CYP3A5基因型,其检测结果与一代测序结果完全一致,重复性好、灵敏度高。结论 HRM方法可以用于CYP3A5基因型检测,为他克莫司的个体化用药提供可靠的评估依据。     

血管内皮生长因子-C及其受体在肾细胞癌中的表达及临床意义

目的探讨肾细胞癌组织中血管内皮生长因子-C（VEGF-C）及其受体（VEGFR-3）的表达水平及其与肿瘤临床、病理因素间的关系。方法采用免疫组织化学方法测定54例肾细胞癌和20例正常肾脏组织中VEGF-C和VEGFR-3蛋白表达水平,观察VEGF-C和VEGFR-3的表达与肿瘤分级、肿瘤分期、淋巴管浸润或淋巴结转移间的相关性。结果肾细胞癌组织中VEGF-C和VEGFR-3蛋白表达水平显著高于正常肾脏组织,两者间差异有统计学意义（P〈0.05）。肿瘤分级、肿瘤分期与VEGF-C和VEGFR-3蛋白的表达强度存在相关性（RR=0.83;0.78）。在伴有淋巴管转移浸润或淋巴结转移的病例中,其VEGF-C和VEGFR-3蛋白的表达明显升高（P〈0.05）。结论通过检测肿瘤组织VEGF-C/VEGFR-3的表达情况,有助于了解肾细胞癌的淋巴管浸润和淋巴结转移的倾向,可能对临床治疗术式选择以及术后辅助治疗选择具有指导意义。     

CYP3A5基因多态性与肾移植后钙调神经蛋白抑制剂慢性肾毒性的相关性

背景：钙调神经蛋白抑制剂是实体器官移植后抗排斥治疗中最重要的一线药物之一,主要通过包括CYP3A5在内的CYP3A亚家族进行代谢。但关于CYP3A5基因多态性与钙调神经蛋白抑制剂慢性肾毒性的相关研究国内外鲜有报道。目的：观察CYP3A5基因多态性与中国人群中钙调磷酸酶抑制剂慢性肾毒性发生的关系。方法：分别收集200例肾移植后出现慢性肾毒性的中国人种患者设为肾毒组;200例肾移植至少12个月后没有出现慢性肾毒性的中国人种患者设为对照组,取两组血样和临床数据。采用聚合酶链反应-限制性内切酶片段长度多态性技术分别检测两组的CYP3A5突变位点基因型。通过统计学分析CYP3A5的基因多态性与钙调神经蛋白抑制剂慢性肾毒性之间的关系。结果与结论：慢性肾毒组中CYP3A5基因型＊1/＊1＋＊1/＊3（显示CYP3A5活性）和＊3/＊3（不显示CYP3A5活性）分别占39.5%（79/200）和60.5%（121/200）;对照组中CYP3A5基因型＊1/＊1＋＊1/＊3（显示CYP3A5活性）和＊3/＊3（不显示CYP3A5活性）分别占28.5%（57/200）和71.5%（143/200）。两组间差异有显著性意义（χ2=9.000,P〈0.05,OR=1.638,95%CI=1.078-2.488）。通过Logistic回归分析CYP3A5＊1/＊1和CYP3A5＊1/＊3是显著的引起CNI慢性肾毒性的危险因素（P〈0.05,OR=1.638,95%CI=1.078～2.488）。提示,CYP3A5的基因多态性可能增加肾移植患者慢性肾毒性的遗传易感性;参与钙调神经蛋白抑制剂慢性肾毒性疾病的发生。     

Taqman-MGB法检测CYP3A5基因rs776746位点单核苷酸多态性及该位点对他克莫司代谢的影响

目的建立检测CYP3A5基因rs776746位点单核苷酸多态性(SNP)的Taqman-MGB实时荧光聚合酶链反应(PCR),并分析该位点对他克莫司药物代谢的影响。方法针对CYP3A5基因rs776746位点设计相应引物及双标记探针,建立并评价检测该位点SNP的Taqman-MGB实时荧光PCR;收集170例服用他克莫司患者的全血DNA样本,用建立的Taqman-MGB实时荧光PCR检测CYP3A5基因型,并分析不同CYP3A5基因型与他克莫司血药浓度剂量比的相关性。结果建立的Taqman-MGB基因分析法能够对CYP3A5 rs776746位点基因型进行高效区分,可检测最低含量为0.01 ng水平的DNA样本,并且具有较好的重复性和特异性,其检测结果与测序结果完全一致。170例患者中CYP3A5*1/*1型18例(10.59%)、CYP3A5*1/*3型65例(38.24%)、CYP3A5*3/*3型87例(51.18%);其中104例异体肾移植患者3种基因型的血药浓度剂量比分别为(52.47±35.96)、(77.79±33.80)、(134.80±79.35)(ng/m L)/(mg·kg-1·d-1),各组之间差异有统计学意义(P0.05)。结论建立了一种敏感性高、特异性好、重复性佳、适用于临床快速检测CYP3A5 rs776746 SNP位点的Taqman-MGB方法。初步分析显示CYP3A5*3基因型的存在会减弱患者对他克莫司的代谢能力。     

The association of CYP2C9 gene polymorphisms with colorectal carcinoma in Han Chinese

BACKGROUND: Cytochrome P450 (CYP) 2C9 is an important enzyme involved in xenobiotics metabolism. This study investigated the association of CYP2C9 gene coding region polymorphisms with colorectal cancer (CRC) in Chinese Han population. METHODS: Four hundred and eighty-three healthy controls and 286 sporadic CRC patients participated in this study. Direct sequencing was used to identify the sequence polymorphisms. RESULTS: We detected the significant association of 2 coding region SNPs, rs1057910 and rs1057911, of CYP2C9 with the risk of developing sporadic CRC for Han Chinese. These 2 SNPs showed a strong linkage disequilibrium (LD) (r(2)=0.97, D'=0.985). Significantly different minor allele frequencies were found for SNPs rs1057910 and rs1057911 between the cases (7% and 7.2%, respectively) and controls (3% and 2.9%, respectively) with adjusted P=0.0004 and 0.0002, respectively. Individuals heterozygous for rs1057910A/C or rs1057911A/T showed 2.589-fold (95% CI: 1.549-4.330) or 2.770-fold (95% CI 1.653-4.643) increased risk of developing sporadic CRC. We did not detect any homozygote minor allele carrier for either rs1057910 or rs1057911 in our study population. The CRC association appeared to be more evident for individuals over age 50 y, for men, and for rectum cancer site. CONCLUSION: There is an association of CYP2C9 coding region polymorphisms with the risk of developing CRC in Han Chinese after genotyping cases and controls recruited from different locations in China.     

CYP3A5 and MDR1 genetic polymorphisms and cyclosporine pharmacokinetics after renal transplantation

BACKGROUND: The immunosuppressive drug cyclosporine (INN, ciclosporin), whose pharmacokinetic characteristics vary greatly among individuals, is a substrate for cytochrome P450 (CYP) 3A and P-glycoprotein, the product of the multidrug resistance 1 (MDR1) gene. Some of the single nucleotide polymorphisms (SNPs) in these genes are associated with deficient protein expression and reduced in vivo activity. We postulated that, in renal transplant recipients, these SNPs could be associated with interindividual variations in cyclosporine pharmacokinetics. PURPOSE: In 106 renal transplant patients, we evaluated retrospectively the effects of 4 MDR1 SNPs [T-129C, C1236T, G2677(T,A), and C3435T] and of the CYP3A5*1/*3 SNP on cyclosporine pharmacokinetic parameters and exposure indices. RESULTS: The CYP3A5*1 allele was present in 8.5% of patients. The MDR1 C1236T, G2677(T,A), and C3435T SNPs were frequent (17.9%, 18.9%, and 33%, respectively, for the variant homozygous genotype) and exhibited incomplete linkage disequilibrium. None of the cyclosporine pharmacokinetic parameters were associated with the CYP3A5 genetic polymorphism. Patients with the wild-type genotype in MDR1 C1236T SNP had slightly but significantly lower dose-adjusted peak drug concentrations (-16%) (P <.02) and dose-adjusted area under the concentration-time curve (AUC) values over the first 4 hours (-14%) (P <.05) as compared with mutated allele carriers. Haplotype analysis including MDR1 C1236T, G2677(T,A), and C3435T SNPs showed no significant association between haplotypes and cyclosporine pharmacokinetics or systemic exposure, although there was a nonsignificant trend toward higher dose-adjusted AUC values over the first 4 hours and AUC over the 12-hour administration interval for the T-T-T haplotype. CONCLUSION: The presence of the CYP3A5 SNP does not explain the high variability of cyclosporine pharmacokinetics in stable renal transplant patients. Despite the weak association found for the MDR1 C1236T SNP, MDR1 SNPs are unlikely to be useful for cyclosporine dose optimization in clinical practice.     

CYP3A4、CYP3A5、COMT及OPRM1基因多态性对术后芬太尼镇痛剂量的影响

目的 探讨代谢酶相关基因（CYP3A4*1G、CYP3A5*3、COMT Val158Met）和药物作用靶点基因（OPRM1rs563649）的多态性与芬太尼术后镇痛剂量个体差异的相关性。方法 选择2018年10月至2020年3月复旦大学附属中山医院收治的择期全麻下行腹腔镜辅助结肠癌根治术患者91例，抽取患者外周静脉血，通过Sanger测序技术检测CYP3A4*1G、CYP3A5*3、OPRM1 rs563649及COMT Val158Met各基因多态性，随访患者术后芬太尼镇痛剂量和视觉模拟评分（VAS）分值，分析基因多态性与腹腔镜术后芬太尼镇痛用量的关系。结果 CYP3A4*1G、CYP3A5*3、OPRM1 rs563649及COMT Val158Met各位点在结肠癌患者中突变频率分别为31.87%、65.93%、9.40%、26.92%。携带CYP3A4*1G/*1G突变纯合子基因型的患者术后第1天、第2天芬太尼消耗量减少（P<0.05）。CYP3A5*3、OPRM1rs563649及COMT Val158Met各基因型的芬太尼术后消耗量差异无统计学意义。CYP3A4*1G...     

CYP3A5 and CYP3A4 but not MDR1 single-nucleotide polymorphisms determine long-term tacrolimus disposition and drug-related nephrotoxicity in renal recipients

The impact of CYP3A and MDR1 gene single-nucleotide polymorphisms on long-term tacrolimus disposition and drug-related toxicity has not been assessed. A study was performed in 95 genotyped recipients by measuring (12 and 4 h) concentration-time curves on day 7; 3, 6 months; 1, 2, 3, 4, and 5 years after transplantation. In contrast to recipients carrying the CYP3A4*1/CYP3A5*1 or CYP3A4*1B/CYP3A5*1 genotypes, dose-corrected tacrolimus exposure almost doubled over 5 years in patients with the CYP3A4*1/ CYP3A5*3 genotype (AUC(0-12 h): from 41.7+/-18.7 to 80+/-39.2 ng h/ml/mg; P<0.05), whereas apparent oral steady-state clearance and dose requirements significantly decreased accordingly. The CYP3A4*1/CYP3A5*1 and CYP3A4*1B/CYP3A5*1 genotypes were significantly more frequently associated with the development of biopsy-proven tacrolimus-related nephrotoxicity than the CYP3A4*1/ CYP3A5*3 genotype (37.5 vs 11.2%; P=0.03 and 42.8 vs 11.2%; P=0.02). The lack of a time-related increase in dose-corrected tacrolimus exposure observed with the CYP3A4*1/CYP3A5*1 and CYP3A4*1B/CYP3A5*1 genotypes is associated with tacrolimus-related nephrotoxicity, possibly as a result of higher concentrations of toxic metabolites.     

XRCC3基因Thr241Met(rs861539)位点单核苷酸多态性与鼻咽癌的相关性

目的:研究XRCC3基因Thr241Met (C/T,rs861539)位点多态性与广东鼻咽癌的相关性.方法:应用PCR方法对127例广州鼻咽癌患者和117例健康对照人群的DNA标本rs861539位点进行扩增、纯化及测序,再结合人群临床资料进行统计学分析.结果:rs861539 C＞T,其中杂合型C/T基因型频率在对照组中分布较高(OR=0.473,95％ CI=0.244～ 0.917,P＜0.05);经年龄及性别分层分析,杂合子在年龄≤30岁(OR＝0.071,95％ CI=0.007～0.722,P＜0.05)以及男性(OR=0.469,95％ CI=0.232～0.947,P＜0.05)人群中在对照组分布较高;而在年龄＞ 30岁以及女性人群中两组间分布均无统计学差异.纯和突变型T/T基因型在两组间分布差异无显著性(OR=1e9,95％ CI=0～∞,P＞0.05),经年龄及性别分层分析,在两组间仍无统计学差异.结论:XRCC3基因Thr241Met (C/T,rs861539)基因多态性可能与鼻咽癌易感性无显著相关性.     

Association of CYP3A5 polymorphisms with hypertension and antihypertensive response to verapamil

In the CYP3A5 gene, the A>G (*3) and G>A (*6) polymorphisms result in severely decreased expression of CYP3A5 enzyme relative to a normal functional allele (*1). We sought to determine if the CYP3A5 genetic polymorphisms were associated with level of blood pressure (BP), risk of hypertension (HTN), and the antihypertensive response to verapamil. A total of 676 normotensive and hypertensive participants (mean age 49+/-8.2 years) from the Hypertension Genes study and 722 patients (mean age 66+/-9 years) from the International Verapamil/Trandolapril Study Genetic Substudy (INVEST-GENES) were genotyped for CYP3A5 to test for associations with BP, HTN, and in the latter cohort, antihypertensive response to verapamil. CYP3A5 haplotypes were determined using PHASE 2, with any allele containing either (*3) or (*6) designated as non functional. In the HTN genes population, there were no significant differences based on the number of functional CYP3A5 alleles, in systolic blood pressure (SBP) or diastolic blood pressure (DBP) among the normotensive whites or blacks (all P> or =0.70) or in allele frequency between normotensives and hypertensives. In INVEST-GENES, when controlled for baseline BP, race, age, and gender, untreated BP in carriers versus non carriers of a CYP3A5 functional allele was 158.2+/-13.7 and 154.8+/-13.7 (P=0.061), respectively. CYP3A5 functional allele status was marginally associated with the SBP response to verapamil in blacks (P=0.075) and Hispanics (P=0.056), but not in whites (P=0.40), with the effect being largely driven by higher SBP in the carriers of two functional alleles. There was no association with DBP response and CYP3A5 allele status. CYP3A5 genotype does not contribute importantly to BP or risk of HTN, but may influence response to calcium channel blockers in populations in which carrier status of two functional alleles is common.     

CYP3A5基因多态性对他克莫司血药浓度的影响

背景：他克莫司属大环内酯类抗生素，具有很强的免疫抑制活性。对预防。肾移植后急性排斥反应、逆转急性排斥反应和慢性排斥反应等具有良好的疗效。但他克莫司治疗窗窄，不同的患者对他克莫司的代谢存在很大的个体差异。 目的：探讨细胞色素P4503A5（CYP3A5）基因多态性对他克莫司血药浓度的影响，以期发现他克莫司在不同个体间吸收、代谢差异的基因背景，建立个体化用药的药物代谢遗传学监控体系。 设计、时间及地点：病例对照观察，于2006—09／2008-03在北京中医药大学附属东直门医院。肾移植中心和解放军第二炮兵总医院临床药理中心完成。 对象：选择北京东直门医院和解放军北京军区总医院正在随访的肾移植术后6个月以上稳定期患者62例，男34例，女28例，年龄25～68岁，体质量45～86妇。同期汉族健康献血者92名为正常对照组，年龄1847岁，男49名，女43名。 方法：患者均使用他克莫司＋霉酚酸酯＋强的松三联免疫抑制治疗，调整剂量使他克莫司血药浓度在5-81μg/L左右，2次／d。除1例患者由服用环孢素A切换为他克莫司1年外，其他患者均肾移植后即服用他克莫司，持续半年以上。 主要观察指标：①用偏振荧光免疫法测定无影响条件下3次他克莫司全血谷浓度指标。②监测血常规、肝。肾功能、血糖等生化指标。③聚合酶链反应方法扩增CYP3A5^＊3目的基因片段，直接测序的方法检测CYP3A5^＊3的多态性。④比较不同基因型之间他克莫司的浓度／剂量比的差异。 结果：CYP3A5^＊3基因6986A→G中，^＊1／^＊1型为6例（9．7％），^＊1／^＊3型为26例（41．9％），^＊3／^＊3型为30例（48．4％）。^＊1／^＊1型和^＊1／^＊3型患者的他克莫司浓度／剂量比明显低于^＊3／^＊3型的患者（P均〈0．01），^＊1／^＊1型纯合子的血药浓度略低于^＊1／^＊3型杂合子，但无统计学意义。患者的肝。肾功能、血糖、血红蛋白等指标在3组之间比较无统计学意义。 结论：CYP3A5^＊3基因多态性与他克莫司的服用剂量密切相关。对含CYP3A5^＊3等位基因的患者在应用他克莫司时应较常规减少用药剂量并注意副作用的发生。而对CYP3A5野生型的。肾移植患者应适当增加服药次数以降低排异反应。     

CYP3A5*3 and CYP3A4*18 single nucleotide polymorphisms in a Chinese population

BACKGROUND: Human cytochrome P450 3A evolved to catalyze the metabolism of numerous common therapy drugs and endogenous molecules. Members of the CYP3A are the majority expressed in human liver and intestine, and there are marked interindividual differences in their protein expression and activity. The activity of CYP3A enzyme in Chinese is highly variable, exceeding 14-fold, and contributes greatly to variation in oral bioavailability and systemic clearance of CYP3A substrates. The genetic factors play an important role in the interindividual variability in CYP3A activity. Detection of CYP3A5 and CYP3A4 variant alleles and knowledge about their allelic frequency in specific ethnic groups are important to lead to individualized drug dosing and improved therapeutics. METHODS: We determined the allelic frequency of the CYP3A5*3 and CYP3A4*18 in a group of 302 Chinese subjects by using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assays. RESULTS: In the group of 302 unrelated individuals, the frequency of the CYP3A5*3 and CYP3A4*18 variant allele in Chinese population were 0.778 (95% CI: 0.754, 0.802) and 0.01 (95% CI: 0, 0.02), respectively. CONCLUSIONS: We developed a simple assay for the detection of the CYP3A4*18 allele and showed that in a Chinese population, CYP3A4*18 and CYP3A5*3 allelic frequencies are similar to that reported previously in Chinese resident in Taiwan. The frequency of the CYP3A5*3 allele in Chinese population is similar to the Japanese but lower than Caucasians. Meanwhile, our findings suggest that an approximate 62% of the Chinese population carrying CYP3A5*3/*3 genotype may appear not to express CYP3A5 protein.     

Pharmacogenetics of acenocoumarol: CYP2C9, CYP2C19, CYP1A2, CYP3A4, CYP3A5 and ABCB1 gene polymorphisms and dose requirements

BACKGROUND AND OBJECTIVE: Acenocoumarol (AC) is a coumarin derivative, vitamin K antagonist anticoagulant drug. It has a narrow therapeutic index and shows large pharmacokinetic and pharmacodynamic interindividual variability. Our objective was to investigate the association between AC dose requirements to achieve a target level of anticoagulation and genetic polymorphisms of genes possibly associated with its metabolism (CYP1A2, CYP2C9, CYP2C19, CYP3A4, CYP3A5) and transport (ABCB1). METHODS: Ninety-six Bulgarian patients treated orally with AC for at least 3 months were included. They were separated into three groups according to their AC dose requirement, i.e. low, medium and high. RESULTS AND DISCUSSION: CYP2C9*1/*3 (associated with an intermediate CYP2C9 activity), CYP2C9*2/*2, and CYP2C9*2/*3 genotypes (associated with a low CYP2C9 activity) were more prevalent in the group with low dose requirement of AC compared with the other two groups (P = 0.003). The frequency of CYP2C9*1/*1 genotype, which is associated with an extensive CYP2C9 activity, was higher in the group of patients with high dose requirements (79%), compared with the groups of the medium and low dose requirements (67% and 21% respectively). In addition, the ABCB1 2677GG/3435CC haplotype was associated with use of lower AC dose, whereas the 2677TT/3435TT and 2677GT/3435TT haplotypes were associated with use of higher AC dose (P = 0.03). The distribution of polymorphisms of other genes did not show significant differences between the three groups. CONCLUSION: In vivo, cytochromes P450 isoforms other than CYP2C9 [corrected] were not significantly associated with dose requirement of AC. In our Bulgarian patients, the presence of CYP2C9*2 or/and CYP2C9*3 alleles, as well as the ABCB1 2677GG/3435CC haplotype were associated with low dose requirement of AC.