中国人CYP1A1和GSTM1基因多态性及其对个体肺癌易感性的联合效应

目的 在中国江苏肺癌患者和对照人群中,检测CYP1A1 Ile/Val,GSTM1 /0遗传多态性的各基因型及其联合基因型的分布,探讨这些基因型与肺癌个体易感性的关系。方法 配对的病例－对照组各106例,静脉血制备DNA。分别应用等位基因特异性（allele-specific,AS)-PCR和多重差别（multidifferential,MD)-PCR,检测CYP1A1 Ile/Val和GSTM1＋／0的等位基因型。结果 CYP1A1少见等位基因Val/Val纯合子及其与GSTM1基因缺失纯合子（0／0）的联合基因个体,与对照常见基因型个体相比,增加了对肺癌的易感性,其相对危险度（odds ratio,OR)分别为4．02（P＝0．03）和9．38（P＝0．04）;GSTM10／0纯合子及其与CYP1A1 Ile/Val杂合子的联合基因型个体,显著增加了肺癌易感性,其OR值分别是1．92（P＝0．019）和3．27（P＝0．01）。结论 中国江苏人群中,少见基因型CYP1A1 Val/Val,GSTM10/0增加了个体肺癌易感性,在肺癌发生中,上述两种易感基因型间存在协同或相乘作用。     

汉族人群谷胱甘肽-S-转移酶M1、T1基因多态性分析

目的 分析汉族人群谷胱甘肽-S-转移酶M1、T1(GSTM1,GSTT1)的基因多态性分布。方法样本为60名唐山地区汉族人群，采用多重等住基因聚合酶链反应(PCR)方法分析GSTM1和GSTT1基因多态性。结果 GSTM1缺失型和GSTT1缺失基因型频率分别为33．3％和11．7％，同时具有GSTM1缺失型和GSTT1缺失型的个体频率为1．7％。结论唐山地区GSTM1,GSTT1基因呈多态性分布，其等位基因和基因型频率不同于其他种族。     

GSTM1、GSTT1缺失和GSTP1基因多态性与原发无精症的相关性研究

目的 探讨谷胱甘肽硫转移酶(glutathione S-transferase,GST)基因家族中GSTM1、GSTT1缺失和GSTP1多态性与汉族人群原发性无精子症的相关性.方法 采用病例对照研究的方法,应用多重PCR及PCR-限制性片段长度多态性技术检测236例汉族原发无精症患者和142名正常生育男性的GSTM1、GSTT1基因缺失和GSTP1基因(Ile/Val)多态性.结果 M1(-/-)和P1(Ile/Val或Val/Val)联合基因型在对照组中分布为24.65％(35/142),高于病例组的15.68％(37/236),差异有统计学意义(P=0.031)；M1(-/-),T1(+/+)和P1(Ile/Val或Val/Val)联合基因型在对照组中分布为12.68％ (18/142),高于病例组的5.51％(13/236),差异有统计学意义(P=0.014).结论 M1(-/-)和P1(Ile/Val或Val/Val)联合基因型以及M1(-/-),T1(+/+)和P1(Ile/Val或Val/Val)联合基因型可能降低男性患无精症的风险.     

细胞代谢解毒酶CYP1A1、GSTM1基因多态性与吸烟对男性肺鳞癌发病的影响

 目的 探讨细胞代谢解毒酶细胞色素P450酶1A1（CYP1A1）、谷胱甘肽S-转硫酶M1（GSTM1）基因多态性和吸烟因素对男性肺鳞癌发病的影响。方法 采用基因芯片技术对125例男性肺鳞癌患者和125例男性健康对照者CYP1A1、GSTM1基因多态性进行检测。结果 CYP1A1 m2位点GG基因型和GSTM1缺失基因型在肺鳞癌组与健康对照者间存在显著性差异(P<0.05 )。吸烟者携带CYP1A1 m2位点至少一个变异G等位基因或携带GSTM1缺失型者患肺鳞癌的危险性进一步显著增加,OR值分别为4.50和3.81(P<0.01)。结论 吸烟与CYP1A1、GSTM1基因多态性与男性肺鳞癌的发生有关。     

云南24个民族群体GSTT1、GSTM1纯合缺失基因型频率的分布

目的：调查GSTT1，GSTM1纯合缺失基因型频率在云南民族群体和地理上的分布。方法：采用聚合酶链式反应的方法，对云南省11个地区24个民族群体进行GSTT1，GSTM1基因型分析。结果：GSTT1和GSTM2纯合缺失基因型频率在民族间的分布分别为0．188－0．633、0．400－0．745，地区间分布分别为0．286－0．583、0．433－0．745；基因频率与民族差异在GSTT1基因中存在统计学上的显著关系，而在GSTM1中无显著关系。基因频率与地区差异在统计学上无显著关系。结论：GSTT1，GSTM1纯合缺失基因型频率在云南各民族群体中存在差异，但在地区分布上比较均一。     

苯及同系物接触者Ⅰ、Ⅱ相代谢酶基因多态性与CYP1A1酶活性关系研究

目的研究职业性接触苯系物与Ⅰ、Ⅱ相代谢酶CYP1A1、CYP2E1、GSTT1和GSTM1基因多态性对CYP1A1酶活性的影响。方法以52例广东省某公司苯系物接触者为接触组,以38例未接触苯系物的“正常人”为对照组,抽提外周血淋巴细胞,Ⅰ、Ⅱ相代谢酶基因多态性检测用PCR和PCR-RLCP方法,CYP1A1酶活性用EROD酶活性表示。结果与对照组比较,苯系物接触组CYP1A1酶活性显著高于对照组（P〈0.01）,但无性别差异。苯接触组中不同Ⅰ、Ⅱ相代谢酶CYP1A1、CYP2E1、GSTT1和GSTM1基因多态性CYP1A1酶活性差异无统计学意义。结论苯作业工人外周血CYP1A1酶的活性受到苯接触的诱导作用,但并未发现受Ⅰ、Ⅱ相代谢酶CYP1A1、CYP2E1、GSTT1和GSTM1基因多态性的影响。     

被动吸烟孕妇胎儿GSTM1、GSTT1及CYP1A1基因多态性对胎儿出生畸形的影响

目的探讨被动吸烟孕妇胎儿谷胱甘肽S转移酶M1(GSTM1)、谷胱苷肽硫转移酶T1(GSTT1)及细胞色素P450(CYP1A1)基因多态性对胎儿出生畸形的影响。方法 2009年1月至2014年12月选取在本院分娩、单胎活产出生畸形的新生儿85名为研究组,另选取同期在本院分娩的185例单胎活产正常新生儿为对照组,采用PCR技术检测两组新生儿GSTM1、GSTT1及CYP1A1基因型,运用多因素模型进行交换作用分析。结果研究组新生儿GSTM1、GSTT1基因缺失型及CYP1A1基因多态突变型频率显著高于对照组(P0.05)。通过多因素模型进行交换作用分析可知,母亲孕期被动吸烟分别与GSTM1、GSTT1基因缺失型及CYP1A1基因多态突变型有正相加模型交互作用。交互效应超额相对危险度(RERI)分别为9.85、8.12、3.26,效应指数(S)分别为1.98、1.79、1.65。结论 GSTM1、GSTT1基因缺失型及CYP1A1基因多态突变型与孕妇孕期被动吸烟存在相加模型交互作用,可能与胎儿先天发育异常的发生有密切关系。     

中国南方汉族人群三种代谢酶基因多态性的分布特征

目的 了解中国南方某汉族人群3种肿瘤易感代谢酶基因多态性的分布特征。方法 以社区为基础的病例－对照研究中对照人群为分析对象，包括有血缘关系内对照290人和无血缘关系外对照404人。结果 3种代谢酶基因多态性在性别、居信地区、胃癌家族史、吸烟史等混杂因素中的频率差异均无显著性，个别组在年龄、饮酒史中的分布有差异，在相关性分析时需调整。CYP1A1 Ile/Val基因型频率为33.43%，Val/Val为5.62%，与中国人、日本人频率接近，但明显高于美洲、欧洲白人及美国黑人；GSTM1缺失基因频率为53.48%，在中国人群中也有一定差异；GSTT1缺失基因频率为45.78%，显著高于白种人和美国黑人。结论 中国南方汉族人CYP1A1突变基因频率和GSTT1缺失基因频率高于其它种族，而GSTM1缺失基因频率与其它种族的差异较小。     

CYP19A1基因 R264C在中国上海BRCA1/2基因突变阴性的遗传倾向乳腺癌中的作用

目的研究CYP19A1基因R264C的（C→T）单核苷酸多态性基因型在上海地区BRCA1／BR-CA2基因突变阴性的遗传倾向乳腺癌人群中的分布及其与乳腺癌发病风险的相关性。方法对114例无BRCA1／2突变的家族性／早发性乳腺癌患者和121名正常对照者进行CYP19A1基因第7外显子的聚合酶链反应扩增，随后进行DNA直接测序鉴定其R264C的单核苷酸多态性基因型，比较基因型分布和发病风险的关系；危险度比值比（odd ratio，OR）及95％可信区间（confidence interval，CI）应用非条件Logistie回归分析计算。结果CYP19A1基因R264C多态的CC、CT、TT基因型在病例组中的分布频率分别为84（77．8％），22（20．4％），2（1、8％）；在对照组的分布频率分别为87（77．7％），24（21、4％），1（0．9％）；在研究的总人群中，CT基因型的频率为20．9％（46／220），TT基因型的频率为1．4％（3／220）。以CC基因型为参照，CT或TT基因型没有显著性地提高乳腺癌的发病危险，其中携带CT基因型风险为（OR=1．16，95％CI：0．53。2．55），携带TT基因型风险为（OR=1．44，95％CI：0．12-17．15）；经过月经状态和身体质量指数分层，也未能发现其与乳腺癌发病的相关性。结论CYP19A1基因R264C的单核苷酸多态性在中国汉族人群中的分布有别于其他种族，有其自身的分布特点；R264C可能与上海地区中国汉族人群乳腺癌发生的遗传易感性无关，尚不足作为低外显率的乳腺癌易感基因位点，不建议作为未来临床基因筛查的候选指标。     

中国广东人CYP2F1基因遗传多态性研究

目的检测广东地区正常人群和鼻咽癌患者中细胞色素P450酶系CYP2F1基因的多态性，并分析该基因遗传多态性与鼻咽癌易感性的关联。方法采用直接测序法检测40例鼻咽癌患者全血标本中CYP2F1基因全部10个外显子的多态性变化。对于等位基因频率较高的多态性位点，进一步采用错配聚合酶链反应．限制性片段长度多态性检测368例鼻咽癌患者和344名正常对照人群中该位点的等位基因频率。结果在40例鼻咽癌样本中，共检测到CYP2F1基因的35个单核苷酸多态性。其中，10个单核甘酸引起编码的氨基酸改变，1个移码突变，15～16bp之间插入C引起移码突变（15-16ins C），该等位基因频率为25％。但病例-对照分析却未能显示该位点突变与鼻咽癌易感的相关性（P〉0．05）。结论中国广东人的CYP2F1基因遗传多态性位点较多，但暂未发现与鼻咽癌的易感性关联的单一多态位点，多个多态性位点或不同基因多态性位点的协同互补作用可能才是鼻咽癌发生发展的关键影响因素。     

GSTM1, GSTT1 and GSTP1 polymorphisms in the Korean population

The isoenzymes of the glutathione s transferase (GST) family play a vital role in phase II of biotransformation of many substances. Using a multiplex polymerase chain reaction and a direct sequencing analysis, the frequencies of GSTM1, GSTT1, and GSTP1 polymorphisms were evaluated in 1,051 Korean male subjects. We found that 53.8% of the individuals had the GSTM1 null genotype and 54.3% had the GSTT 1 null genotype. The genotypic distribution of GSTP1 was Ile105/Ile105 in 68.4%, Ile105/Val105 in 29.1% and Val105/Va105 in 2.5%. The most frequently observed combination of GSTM1, GSTP1 and GSTT1 genotypes was Null type/Ile105/Ile105/Null type, while the combination of Non-null type/Val105/Val105/Non-Null type was not observed. We found that the genotype distributions of three GST isoenzymes in the Koreans are similar to those reported in Asians and previously reported Koreans. We believe our results, which are represented by a large population, are reliable estimates of the frequencies of the polymorphic GST alleles in the Koreans and will help future researches on GST polymorphisms.     

Polymorphisms in glutathione S-transferases GSTM1, GSTT1 and GSTP1 and cytochromes P450 CYP2E1 and CYP1A1 and susceptibility to cirrhosis or pancreatitis in alcoholics

Excessive alcohol consumption may cause the development of pathologies in the liver and pancreas and various digestive tract cancers. The enzymes GSTM1, GSTT1, GSTP1, CYP1A1 and CYP2E1 are involved in the bioactivation and detoxification of a variety of xenobiotics present in food, organic solvents, tobacco smoke, drugs, pesticides, environmental pollutants and alcoholic drinks. Polymorphisms in the genes coding for these enzymes have been associated with susceptibility to different diseases, including ethanol-related diseases. To investigate whether these polymorphisms represent risk-modifying factors for ethanol-related diseases, a study was conducted involving 120 Brazilian alcoholics and 221 controls with similar ethnic backgrounds. The distribution of alcoholics groups was as follows: 65 with liver cirrhosis, 14 with chronic pancreatitis and 41 without cirrhosis or pancreatitis. The data revealed that carriers of the rare GSTP1 Val allele were at higher risk of liver cirrhosis and pancreatitis, since we found higher frequencies of the Val/Val genotype in alcoholics with liver cirrhosis (15.4%) and pancreatitis (28.6%) in comparison with alcoholics without disease (7.3%). No differences were found in the prevalences of the GSTM1 and GSTT1 null genotypes between alcoholics and the controls and no association was found between the rare CYP2E1 c2 allele and liver cirrhosis and pancreatitis. However, when the mutant CYP1A1 allele was compared between alcoholics and controls, the m2/m2 genotype was more prevalent in the liver cirrhosis alcoholics (7.7%) than in the controls (1.4%) and this difference was statistically significant (P = 0.03, OR = 5.33). In conclusion, our data indicate an association between occurrence of the Val/Val GSTP1 genotype and chronic pancreatitis and an association between the m2/m2 CYP1A1 genotype and alcoholic liver cirrhosis. This could indicate that persons with these genotypes are genetically more prone to the development of alcoholic pancreatitis and alcoholic cirrhosis, respectively.     

A polymorphism in the CYP17 gene and intrauterine fetal growth restriction

Intrauterine fetal growth restriction is a multifactorial disorder, and its aetiology includes both environmental and genetic components. We aimed to investigate whether maternal genetic polymorphisms of metabolic enzymes affects fetal growth and pregnancy duration. Genomic DNA was obtained from 134 women who experienced singleton deliveries beyond 24 weeks of gestation. Maternal age, birth weight, gestational age at birth and frequencies of fetal growth restriction, prematurity and pregnancy-induced hypertension were compared among genotypic subgroups of cytochrome p450 (CYP) and glutathione S-transferase (GST) genes. The polymorphisms of CYP1A1 (MspI), CYP17 (MspAI) and GSTP1 (BsmAI) genotypes, and the presence or absence of GSTM1 and GSTT1 genes were analysed by PCR-based methods. The frequency of fetal growth restriction (<10th percentile/<-1.5 SD; 22.7%/11.4%) in 44 women who were homozygous for the A1 allele (A1A1) of CYP17 was significantly higher than that (7.8%/2.2%) in 90 women who carried the A2 allele (A1A2/A2A2) of CYP17 (P < 0.05), with an odds ratio =3.41 (95% confidence interval = 1.18-9.84). The gestational age at birth (mean +/- SD, 37.5 +/- 3.1 weeks) in 67 women with GSTM1 null genotype was significantly lower than that (38.5 +/- 2.4 weeks) in 67 women who carried GSTM1 (P < 0.05). The polymorphism of CYP17 that encodes the cytochrome p450c17alpha enzyme might be associated with the pathophysiology underlying fetal growth restriction.     

Possible risk modification by CYP1A1, GSTM1 and GSTT1 gene polymorphisms in lung cancer susceptibility in a South Indian population

Susceptibility to lung cancer has been shown to be modulated by inheritance of polymorphic genes encoding cytochrome P450 1A1 (CYP1A1) and glutathione S transferases (GSTM1 and GSTT1), which are involved in the bioactivation and detoxification of environmental toxins. As the incidence of lung cancer is known to differ according to ethnicity, we have conducted a case-control study of 146 South Indian lung cancer patients along with 146 healthy controls, to assess any association between CYP1A1, GSTM1 and GSTT1 polymorphisms, either separately or in combination, with the likelihood of development of lung cancer in our population. The current weight of evidence from our study indicated that the frequency of CYP1A1 MspI homozygous variant alleles was significantly higher in cases (OR=3.178). We observed a considerable difference in the GSTT1 null deletion frequency in this population when compared with other populations (OR=2.472, 95% CI: 1.191–5.094, P=0.014). There was no relative risk in GSTM1 null genotype when analysed singly (P=0.453). Considering genotype combinations, risk of lung cancer increased remarkably significantly in individuals having one variant allele of CYP1A1, GSTM1, or GSTT1, suggesting gene–gene interactions. Rare genotypic combinations (such as CYP1A1 wild GSTM1 or GSTT1 either null; CYP1A1 variant both GSTM1 and GSTT1 present; CYP1A1 variant GSTM1 or GSTT1 either null), were at higher risk compared to the reference group. Moreover, patients who had smoked <20 pack years and harboured the CYP1A1 variant allele or the GSTT1 null genotype also had a significant risk of lung cancer. Hence our study—the first to analyse a South Indian population—suggests the importance of combined CYP1A1, GSTM1 and GSTT1 polymorphisms in the development of smoking-induced lung cancer.     

贵州三个少数民族谷胱甘肽S-转移酶M1、T1和P1基因多态性

目的研究贵州省从江县侗族、威宁县彝族、荔波县瑶族的谷胱甘肽S-转移酶基因(GSTs)多态性。方法在隔离自然人群(从江县侗族108人、威宁县彝族104人、荔波县瑶族109人)中,采用多重等位基因特异聚合酶链反应方法分析GSTM1和GSTT1基因多态性,采用聚合酶链反应及限制性片段长度多态性方法分析GSTP11578(A→G)基因多态性。结果贵州省从江县侗族、威宁县彝族、荔波县瑶族的GSTM1和GSTT1纯合缺失基因型频率分别为59.6%～71.2%、39.4%～72.5%。其GSTP11578(A→G)基因型频率分别是:AA为63.3%～75%、AG为23.2%～35.8%、GG为0～1.9%。等位基因频率:A为81.2%～86.6%,G为13.4%～18.8%。结论GSTT1基因型频率在贵州从江侗族、威宁彝族、荔波瑶族中存在差异,其分布特征可能与人群中不同种族以及同一种族不同民族相关。     

Polymorphisms of the genes encoding the GSTM1, GSTT1 and GSTP1 in Korean women: no association with endometriosis

Endometriosis, one of the most common gynaecologic disorders, shows significantly elevated prevalence in industrial areas and there is also a possible genetic predisposition. Glutathione-S-transferases (GSTs) are enzymes involved in the metabolism of many disease-causing carcinogens and mutagens that are present in human environments. An association between the incidence of endometriosis and the GST genotypes of patients has been suggested. The objective of the present study was to investigate whether the polymorphisms of GSTM1, GSTT1 and GSTP1 are related to endometriosis. Blood samples were available from 259 controls and 194 patients with advanced endometriosis diagnosed by both pathology and laparoscopic findings. The proportion of the GSTM1, GSTT1 and GSTP1 genotypes of the control group were comparable to other populations. There was no significant evidence that the distribution of the GSTM1 and GSTT1 genotype differed between the patients and the controls, with an allelic odds ratio (OR)=1.074 [95% confidence interval (CI)=0.737-1.564] and 1.239 (95% CI = 0.853-1.799), respectively. Also, there was no significant difference in the proportion of GSTP1 genotypes between the women with endometriosis and the control group with the OR = 0.823 (95% CI = 0.536-1.264). The higher risk alleles were contended as GSTM1, GSTT1 null mutation and GSTP1 Ile105Ile polymorphism. There was no significant increase in the risk of endometriosis as the number of higher risk alleles of the GST family increased. In conclusion, our findings suggest that the GSTM1, GSTT1 and GSTP1 genetic polymorphisms are not associated with the development of endometriosis in Korean women.     

Association between polymorphisms in the biometabolism genes CYP1A1, GSTM1, GSTT1 and GSTP1 in bladder cancer

Numerous enzymes, including Cytochrome P450s (phase I) and Glutathione-S-transferases (phase II), are involved in the metabolic activation and detoxification of carcinogens. Epidemiological studies have consistently demonstrated that bladder cancer is strongly associated with cigarette smoking, and the risk for the development of this neoplasia may be modified by individual differences in carcinogen-metabolizing genes. We investigated the relationship between polymorphisms in the CYP1A1, GSTM1, GSTT1, and GSTP1 genes in a case–control study with 100 bladder cancer patients and 100 controls matched for age, gender, race, and smoking status. The GSTM1, GSTT1, CYP1A1 (A2455→G), and GSTP1 (A313→G) genotypes were determined using a multiplex PCR, an allele specific PCR, and a restriction fragment length polymorphism-PCR method. The present case–controlled association study did not detect any positive or negative association for the GSTM1 and GSTP1 genes [odds ratios (OR) = 1.35; 95% confidence interval (CI) = 0.76–2.41 and OR = 0.75; 95% CI = 0.41–1.38, respectively]. Notably, the genes GSTT1 and CYP1A1 exhibited a statistically significant association with bladder cancer (OR = 1.77; 95% CI = 1.01–3.12 and OR = 1.99; 95% CI = 1.07–3.73). No differences for GSTM1 and GSTP1 genotype prevalence between the bladder cancer cases and the controls were observed, however, the null genotype for the GSTT1 gene and the A/G and G/G variants of the CYP1A1 gene may contribute to the development of bladder cancer.     

GSTT1 null genotype is a risk factor for diabetic retinopathy in Caucasians with type 2 diabetes, whereas GSTM1 null genotype might confer protection against retinopathy

Aim: Substantial data indicate that oxidative stress is involved in the development of diabetic retinopathy (DR). The aim of the present study was to investigate whether the genetic polymorphisms: polymorphic deletions of glutathione S-transferases M1 (GSTM1) and T1 (GSTT1) and Ile105Val of the GSTP1 are associated with DR in Slovenian patients with type 2 diabetes.Methods: In this cross sectional case-control study 604 unrelated Slovene subjects (Caucasians) with type 2 diabetes mellitus were enrolled: 284 patients with DR (cases) and the control group of 320 subjects with type 2 diabetes of more than 10 years’ duration who had no clinical signs of DR. Genotypes were determined by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). Results: In our study, the deletion of the GSTM1 was found less frequent in cases with DR than in the controls (27.5% versus 44.4%; P < 0.001), whereas the deletion of GSTT1 was found significantly more often in cases than in the controls (49.3% versus 29.7%;P < 0.001). We did not find statistically significant differences in the genotype distribution in GSTP1 (Ile105Val) polymorphism between cases and controls (40.5% versus 46.0%). Conclusions: We may conclude that individuals homozygous for the deletion of GSTT1 are at an ≈ 2-fold-greater risk of DR, whereas the GSTM1 deficiency is associated with lower frequency of DR in type 2 diabetics.