云南籍几个正常人群间GSTM1基因多态性的比较研究

目的: 针对云南曲靖地区宣威县、富源县及非曲靖地区3组正常人群进行GSTM1基因型多态性的比较研究.方法:采用聚合酶链反应(Polymerase chain reaction,PCR)技术对相关人群进行基因型鉴定.结果:GSTM1纯合缺失基因型(0/0)的频率在宣威人群为63.6%(n＝33),富源人群为64.5%(n＝31),非曲靖人群为68.5%(n＝35).结论:GSTM1基因型多态性在3个正常人群中的分布情况均一.该研究为了解特定地区肺癌与外源物代谢解毒基因之间的可能联系提供了一些基础数据.     

GSTM1、GSTT1基因多态性与四川北部地区肺癌易感性关系的研究

目的:探讨谷胱苷肽硫转移酶M1(GSTM1)和T1(GSTT1)基因多态性与四川北部地区汉族人群肺癌易感性的关系。方法:采用病例对照研究和聚合酶链式反应(PCR)技术检测四川北部地区肺癌病人125例和健康对照组125例中GSTM1(-)和GSTT1(-)的频率,评价两基因型及两基因的交互作用与肺癌易感性的关系。结果:GSTM1(-)在肺癌组和对照组分布频率分别为58.4%和56.8%,单因素回归分析未见统计学差异(OR=1.06,95%CI:0.639-1.757,P=0.822);GSTT1(-)在肺癌组和对照组分布频率分别为45.6%和44.8%,单因素回归分析未见统计学差异(OR=0.968,95%CI:0.588-1.593,P=0.899),GSTM1(-)和GSTT1(-)联合并未增加肺癌风险(OR=1.084,95%CI:0.536-2.192,P=0.823)。结论:GSTM1及GSTT1各基因型单独或联合作用都不是四川北部地区汉族人群肺癌的风险因素。     

广西扶绥县肝癌高发家系谷胱甘肽转硫酶GSTM_1和GSTT_1基因多态性的研究

目的探讨广西扶绥县肝癌高发区壮族人群谷胱甘肽转硫酶GSTM1和GSTT1的基因多态性在肝癌家族聚集性中的作用,以及一级亲属与先证者之间HCC易感性的关系。方法采用病例-对照研究方法,收集21个广西扶绥县壮族肝癌家系76例,以及该地区21个对照家系68例,采用多重PCR技术和凝胶成像分析方法,对入选者GSTM1和GSTT1基因型进行检测,用ELISA法检测HBsAg,并将实验结果与临床资料相结合,进行统计学分析。结果①GSTM1基因空白型在肝癌家系组、对照家系组之间的频率分别为67.1%和36.8%(P=0.000);GSTT1基因空白型在肝癌家系组、对照家系组之间的频率分别为40.8%和19.1%(P=0.005);GSTM1和GSTT1基因同时缺失在肝癌家系组、对照家系组的频率分别为31.6%和2.9%(P=0.000)。②将GSTM1及GSTT1基因同时表达型为基准计算两基因联合作用的危险度,GSTM1基因缺失GSTT1基因表达型、GSTM1基因表达GSTT1基因缺失型、GSTM1基因及GSTT1基因联合缺失型的OR值分别为0.102、0.210和3.092。③GSTM1基因空白型在先证者与其直系亲属之间的频率分别为71.4%和65.5%(P=0.620),GSTT1基因空白型在先证者与其直系亲属之间的频率分别为47.6%和38.2%(P=0.454)。GSTM1和GSTT1基因同时缺失在先证者与其直系亲属之间的频率分别为33.3%和30.9%(P=0.839),差异均无统计学意义(P>0.05)。结论①GSTM1和GSTT1基因的多态性与肝癌家族聚集性相关;②GSTM1和GSTT1基因联合缺失与HCC的发生呈显著正相关,且两基因可能具有协同作用;③直系亲属与先证者HCC发生率无差别。     

广西扶绥人群GSTM1和GSTT1基因多态性与肝癌易感性关系的研究

目的:探讨GSTM1和GSTT1基因多态性与肝癌易感性关系,以及基因与基因间的相互作用.方法: 应用病例-对照分析研究,采用多重PCR技术,对广西扶绥100例肝细胞癌患者、60例正常人群的GSTM1和GSTT1基因型进行检测.将实验结果与临床资料结合进行统计学分析.结果: GSTM1基因空白型在HCC组和正常对照组中的频率分别为59.0%、68.3%(P>0.05);HCC组GSTT1基因缺失频率(33.0%)显著高于正常对照组(18.3%);GSTM1和GSTT1基因同时缺失在肝癌组和对照组中的频率分别为22.0%和3.3%,两者差异有统计学意义.结论:1)GSTM1和GSTT1基因的缺失是通过遗传获得.2)GSTT1基因缺失是HCC的易感因素.3)GSTM1和GSTT1基因联合缺失与HCC的发生呈显著正相关,且两基因具有协同作用,可作为HCC高危人群筛选的有用指标.     

GSTT1和GSTM1基因缺失多态与胃癌易感性

目的　探讨与致癌物解毒有关的谷胱甘肽转硫酶 (GST) T1和 M1基因遗传缺失多态与胃癌易感性的关系。方法　采用病例对照分子流行病学研究方法 ,以 PCR技术对福建省福州市 92例胃癌病例和 92例正常对照者的 GSTT1和 GSTM1基因型进行检测。结果　 GSTT1基因在胃癌病例和对照组中的缺失率分别为 5 3.3%和41.3% ,差异无显著性 (x2 =2 .6 4,P=0 .10 4)。而 GSTM1基因在胃癌病例和对照组中的缺失率分别为 6 9.6 %和5 2 .2 % ,差异具有显著性 (x2 =5 .84,P=0 .0 15 7)。携带 GSTM1(- )基因型者发生胃癌的危险性是携带 GSTM1( )基因型者的 2 .1倍 (OR=2 .10 ,95 % CI=1.10～ 4.0 1)。联合分析表明 ,GSTT1和 GSTM1基因之间可能存在联合作用 ,携带 GSTT1(- )和 GSTM1(- )基因型者发生胃癌的危险性高于携带 GSTT1( )和 GSTM1( )基因型者 (OR=4.6 7,95 % CI=1.5 5～ 14.41)。结论　 GSTM1基因缺失可能是胃癌发病的危险性因素之一     

四川北部地区肺癌患者GSTT1基因多态性分析

目的:了解四川北部地区汉族肺癌人群GSTT1基因多态性状况,与其他地区人群人种进行比较。方法:采用聚合酶链式反应(PCR)技术检测该地区肺癌患者GSTT1基因缺失〔GSTT1(-)〕频率。结果:本地区肺癌患者GSTT1(-)频率为45%(45/100),其中纯和缺失率女性和男性分别为52.0%(13/25)和42.7%(32/75),χ2=0.660,P=0.417;鳞癌38.1%(16/42),腺癌48.0%(12/25),χ2=0.632,P=0.427;吸烟者44.4%(28/63),不吸烟者45.9%(17/37),χ2=0.021,P=0.884。结论:本地区肺癌患者GSTT1基因缺失频率高于欧美,与亚洲多中心研究结果类似,缺失频率与性别、病理类型及是否吸烟无关。     

广西扶绥县肝癌高发家系谷胱甘肽转硫酶GSTM1和GSTT1基因多态性的研究

目的探讨广西扶绥县肝癌高发区壮族人群谷胱甘肽转硫酶GSTM1和GSTT1的基因多态性在肝癌家族聚集性中的作用,以及一级亲属与先证者之间HCC易感性的关系。方法采用病例一对照研究方法,收集21个广西扶绥县壮族肝癌家系76例,以及该地区21个对照家系68例,采用多重PCR技术和凝胶成像分析方法,对入选者GSTM1和GSTT1基因型进行检测,用ELISA法检测HBsAg,并将实验结果与临床资料相结合,进行统计学分析。结果（1）GSTM1基因空白型在肝癌家系组、对照家系组之间的频率分别为67．1％和36．8％（P=0．000）;GSTT1基因空白型在肝癌家系组、对照家系组之间的频率分别为40．8％和19．1％（P=-0．005）;GSTM1和GSTT1基因同时缺失在肝癌家系组、对照家系组的频率分别为31．6％和2．9％（P=0．000）。②将GSTM1及GSTT1基因同时表达型为基准计算两基因联合作用的危险度,GSTM1基因缺失GSTT1基因表达型、GSTM1基因表达GSTT1基因缺失型、GSTM1基因及GSTT1基因联合缺失型的OR值分别为0．102、0．210和3．092。（3）GSTM1基因空白型在先证者与其直系亲属之间的频率分别为71．4％和65．5％（P=0．620）,GSTT1基因空白型在先证者与其直系亲属之间的频率分别为47．6％和38．2％（P=0．454）。GSTM1和GSTT1基因同时缺失在先证者与其直系亲属之间的频率分别为33．3％和30．9％（P=-0．839）,差异均无统计学意义（P〉0．05）。结论（1）GSTM1和GSTT1基因的多态性与肝癌家族聚集性相关;（2）GSTM1和GSTT1基因联合缺失与HCC的发生呈显著正相关,且两基因可能具有协同作用;③直系亲属与先证者HCC发生率无差别。     

广西鼻咽癌患者解毒酶基因GSTM1和GSTT1缺失的研究

目的研究鼻咽癌高发区鼻咽癌患者对化学致癌物的遗传易感性。方法应用PCR技术,研究鼻咽癌患者与对照组健康者人体主要解毒酶谷胱甘肽硫转移酶(GST)M1(GSTM1)和GSTT1基因缺失多态性,估计其与鼻咽癌地区性高发的相关性。结果鼻咽癌高发区居民GSTM1或GSTT1缺失率偏高,分别为47.4%(64/135)和40.7%(55/135)。鼻咽癌患者GSTM1或GSTT1缺失率分别为61.5%(56/91)和59.3%(54/91),显著高于对照组(P<0.05,P<0.01)。特别是GSTM1和GSTT1两种基因双缺失者,在病例组与对照组间差异有极显著性(χ2=12.533,P=0.002)。结论鼻咽癌高发区人群及患者GSTM1和GSTT1高频联合缺失,可能为相应的环境致癌化学毒物遗传易感性和鼻咽癌患者的地区聚集原因。     

谷胱苷肽S转硫酶T1、M1和P1基因多态性与结直肠癌易感性的关系

目的研究谷胱苷肽S转硫酶T1、M1和P1(GSTT1、GSTM1和GSTP1)多态性与结直肠癌易感性的关系。方法在江苏省进行了1个病例—对照研究(结直肠癌患者315例,人群对照439例),调查研究对象的生活习惯,抽取静脉血,提取白细胞DNA,以多重PCR技术检测GSTT1和GSTM1基因缺失,PCR-RFLP技术检测GSTP1基因单核苷酸多态(第104密码子A→G)。结果①在结直肠癌组和正常组GSTT1和GSTM1基因缺失频率分别为55.24%、57.31%和72.70%、73.29%、差异无显著性。②在结直肠癌组GSTP1 A/A、A/G和G/G基因型分布频度分别为57.51%、36.74%和5.75%;对照组分别为63.70%、31.05%和5.25%,2组之间差异无显著性(χ2 MH=2.993,P=0.224)。与GSTP1 A/A基因型携带者相比,G/G基因型者发生结直肠癌的危险性无显著升高,其性别、年龄、吸烟、饮酒习惯调整后的OR为1.09(95%CI:0.79~1.51)。结论GSTT1、GSTM1基因缺失型和GSTP1 G/G基因型与结直肠癌的易感性无显著相关。     

GSTM1、GSTT1基因多态性和吸烟与膀胱癌关系的病例对照研究

目的:应用全人群为基础的病例对照研究探讨GSTM1、GSTT1基因多态性和吸烟与膀胱癌危险性的关系。方法:采用多重PCR方法对404例正常对照和414例膀胱癌病例的基因组DNA进行GSTM1和GSTT1基因分型,应用非条件logistic回归分析方法进行统计分析。结果:与携带GSTM1( )基因型者比,GSTM1(-)基因型的男、女性患膀胱癌危险性分别为1.66(95%CI:1.18～2.33)和1.08(95%CI:0.59～1.98)。同样携带GSTM1(-)基因型,吸烟者比不吸烟者患膀胱癌的危险性更加明显。与不吸烟且携带GSTM1( )基因型男性比,GSTM1(-)基因型的目前吸烟者的OR值为2.99(95%CI:1.56～5.74),而携带GSTM1(-)基因型同时吸烟年限≥40年者OR为4.33(95%CI:2.14～8.73)。尽管女性吸烟例数较少,但携带GSTM1(-)基因型的吸烟女性患膀胱癌危险性显著高于不吸烟的GSTM1( )基因型者,OR值为6.72(95%CI:1.69～26.80)。与不吸烟且携带GSTT1( )基因型男性相比,携带GSTT1(-)基因型的吸烟者患男性膀胱癌危险的OR值为1.38(95%CI:0.79～2.42)。携带GSTT1(-)基因型的吸烟女性患膀胱癌危险性是不吸烟的GSTT1( )基因型者的3.04倍(95%CI:0.77～12.01)。结论:GSTM1(-)基因型能显著增加男性患膀胱癌的风险,该基因型与吸烟可能有一定的联合作用。GSTT1基因型可能与上海市区男、女性膀胱癌无关。     

GSTM1 and GSTT1 Genetic Polymorphisms and Breast Cancer Risk in Selected Filipino Cases

Background: The association of genetic polymorphisms with cancer development has been shown to be race- andtumor site-specific. Thus, this study aimed to determine whether polymorphisms in the GSTM1 and GSTT1 genesare associated with breast cancer among selected Filipinos. Methods: A total of 136 histologically confirmed breastcancer cases were age- and sex-matched with 136 clinically healthy controls. Genomic DNA extracted from bloodsamples of participants were screened for GSTM1 and GSTT1 genetic polymorphisms by multiplex PCR. Results:The frequency of null genotypes among the cases (GSTM1: n=78; 57.4%; GSTT1: n=61; 44.9%) was not significantlydifferent (p>0.05) from the controls (GSTM1: n=93; 68.4%; GSTT1: n=59; 43.4%). It was also demonstrated that riskfor breast cancer was increased in passive smokers carrying the GSTM1 null (OR=2.56; 95% CI=1.38-4.75) or GSTT1positive (OR=2.00; 95% CI=1.05-3.83) genotypes. Moreover, risk was decreased in alcohol users carrying the GSTT1null (OR=0.39; 95% CI=0.16-0.97) genotype. Conclusion: This study suggests that variants of GSTM1 and GSTT1may not be risk factors for breast cancer development among Filipinos. However, the risk may be increased when thesegenotypes were combined with lifestyle or environmental factors.     

Variations in glutathione-S-transferase genes influence risk of chronic myeloid leukemia

Glutathione S-transferases (GSTs) are phase II enzymes that detoxify hazardous xenobiotics including carcinogens. Inter-individual variations in GSTM1 and GSTT1 loci have been associated with several types of cancer, including leukemias. In this study, we investigated the possible association between GSTM1 and GSTT1 polymorphisms and susceptibility to chronic myeloid leukemia (CML) in a Turkish population. In a case-control study, 106 CML patients and 190 healthy controls were evaluated for GSTM1 and GSTT1 polymorphisms. GSTM1 null (GSTM1(-)) genotype frequencies in CML cases and controls were 45.3% and 42.6%, respectively. GSTT1 null (GSTT1(-)) genotype frequencies were 44.3% and 18.4%, respectively. The frequency of the GSTT1(-) genotype among CML patients was significantly higher than in controls [odds ratio (OR) 3.53, 95% confidence interval (CI) 2.08-6.00; P < 0.0001]. Individuals with the GSTM1(-) genotype did not have increased risk of CML [OR: 1.11; 95% CI: 0.69-1.80; P = 0.714]. The combined GSTM1(-)/GSTT1(-) genotype was significantly associated with risk of CML compared to the GSTM1(+) /GSTT1(+) genotype which was most frequent in both cases and controls [OR: 9.47; 95% CI: 3.61-24.87]. Similar findings have only been obtained in Turkish and Indian populations but not elsewhere. The GSTM1(+) /GSTT1(-) genotype was associated with a 2.5-fold increased risk compared with the GSTM1(-)/GSTT1(+) genotype, the second most frequent genotype (OR; 2.46; 95% CI: 1.17, 5.20), suggesting a complex interaction between GSTM1 and GSTT1. Our results indicate an association between the GSTT1(-) genotype, either alone or in combination with GSTM1(-) genotype, and risk of CML, suggesting a possible interaction between GSTM1 and GSTT1. These findings, which are possibly restricted to Turkey and India, warrant further research.     

Glutathione S-transferase M1 (GSTM1) and T1 (GSTT1) Polymorphisms and Lung Cancer Risk among a Select Group of Iranian People

Objective(s): Lung cancer, caused primarily by smoking, is one of the leading determinants of mortality throughoutthe world. Here we investigated the effects of polymorphisms in two enzymes, i.e., GSTT1 and GSTM1, related tothe antioxidant defense line against carcinogens associated with lung cancer among a select group of Iranian people.Materials and Methods: One hundred and twenty lung cancer patients from two referral centers in Tehran, Iran, wererecruited for comparison with 120 healthy controls. Genomic DNA was extracted from the FFPE tumor tissues ofthe select cases and peripheral blood buffy coats of healthy controls. The polymorphisms of GSTT1 and GSTM1 wereinvestigated by multiplex polymerase chain reaction. Results: With the 240 samples studied, no specific relationshipwith lung cancer was discerned for the GSTM1 (P=0.35; OR=1/33; 95% CI=0.79-2.25) polymorphism, but the GSTT1(P=0.005; OR=2.4; CI=1.32-4.35) gene polymorphism revealed a notable association on logistic regression, takinginto account age and sex factors. Furthermore, the GSTT1 genotype distribution in patients with LSCC was differentfrom that of healthy cases (P=0.006; OR=3.11; CI=1.38-7.04). The risk of developing lung cancer with the T0M1genotype was 3.46 times higher than with T1M1 genotype (P=0.002; OR=3.46; CI=1.61-7.46). Moreover, the risk ofdeveloping LSCC cancer in people with T0M1 genotypes was significantly elevated (P=0.004; OR=4.5; CI=1.62-12.52).Conclusion: Unlike GSTM1, the GSTT1 genotype distribution is associated with the incidence of lung cancer in Iranianpeople. Different types of lung cancer appear to show various correlations with GST polymorphisms in this regard.     

Glutathione-S-transferase (GSTM1, GSTT1) Null Phenotypes and Risk of Lung Cancer in a Korean Population

Purpose: The aim of this study was to evaluate any association of GSTM1 and GSTT1 null genotypes withthe risk of lung cancer in a South Korean population. Methods: We conducted a large-scale, population-basedcase-control study including 3,933 lung cancer cases and 1,699 controls. Genotypes of GSTM1 and GSTT1 weredetermined using real-time polymerase chain reaction. Results: In logistic regression analysis adjusted for age andsmoking, we did not find any association between GSTM1 or GSTT1 and LC risk in women. However, in men,the GSTM1 and GSTTI null genotypes were borderline associated with risk (OR=1.18, 95% CI=0.99-1.41 forGSTM1, OR=1.18, 95% CI=0.99-1.41 for GSTT1), and combined GSTM1 and GSTT1 null genotypes conferredan increased risk for LC in men (OR=1.39, 95% CI=1.08–1.78). The OR for the GSTT1 null genotype was greaterin subjects aged 55 years old or younger (OR=1.45, 95% CI=1.09-1.92 for men; OR=1.36, 95% CI=0.97–1.90for women), than in those over age 55 (OR=1.03, 95% CI=0.83-1.27 for men; OR=0.86, 95% CI=0.66–1.12 forwomen) in both genders (p for interaction <0.05). Conclusions: In the Korean population, the GSTM1 andGSTT1 null genotypes are risk factors for LC in men; the GSTT1 null genotype has a more prominent effecton LC risk in younger people (age 55 years and under) than in older individuals.     

Lack of Associations between Genetic Polymorphisms in GSTM1, GSTT1 and GSTP1 and Pancreatic Cancer Risk: A Multi-Institutional Case-Control Study in Japan

Background: We aimed to evaluate the role of genetic polymorphisms in tobacco carcinogen-metabolizinggenes and their interactions with smoking in a hospital-based case-control study of Japanese subjects. Materialsand Methods: We examine the associations of pancreatic cancer risk with genetic polymorphisms in GSTM1,GSTT1 and GSTP1, phase II enzymes that catalyze the conjugation of toxic and carcinogenic electrophilicmolecules. The study population consisted of 360 patients and 400 control subjects, who were recruited fromseveral medical facilities in Japan. Unconditional logistic regression methods were used to estimate odds ratios(ORs) and 95% confidence intervals (CIs) for the associations between genotypes and pancreatic cancer risk.Results: Among the control subjects, the prevalence of the GSTM1-null genotype and the GSTT1-null genotypewas approximately 56% and 48%, respectively. Cases and controls were comparable in terms of GSTM1 andGSTT1 genotype distributions. Neither of the deleted polymorphisms in GSTM1 and GSTT1 was associated withthe risk of pancreatic cancer, with an age- and sex-adjusted OR of 0.99 (95%CI: 0.74-1.32) for the GSTM1-nullgenotype, and 0.98 (95%CI: 0.73-1.31) for the GSTT1-null genotype. The OR was 0.97 (95%CI: 0.64-1.47) forindividuals with the GSTM1 and GSTT1-null genotypes compared with those with the GSTM1 and GSTT1-present genotypes. No synergistic effects of smoking or GST genotypes were observed. Conclusions: Our resultsindicate no overall association between the GSTM1 and GSTT1 deletion polymorphisms and pancreatic cancerrisk in the Japanese subjects in our study.     

IGlutathione S-transferase (GSTM1 and GSTT1) Polymorphisms in Cervical Cancer in Northeastern Thailand

To evaluate the relationships between genetic polymorphisms of the GSTs (GSTM1 and GSTT1) and cervicalcancer, the null genotype of each gene was studied in squamous cell cervical cancer (SCCA) patients (n=90) andcontrols (n=94) in Northeast Thailand. The prevalence of the GSTM1-null genotype in the controls and SCCApatients was 59.6% and 60.0%, respectively, whereas those of the GSTT1-null genotype in the control andSCCA patients was 40.4% and 46.7%, respectively. Neither of the GST-null genotypes increased the risk forSCCA (p>0.05); however, the combination of the GSTM-1 and GSTT1-null genotypes showed a non-significanttrend to an increased risk for developing cervical cancer with an adjusted OR of 2.7 (95%CI=0.8-9.0, p=0.10).Genetic polymorphisms of GSTM1 and GSTT1 were not significant risk factors for cervical cancer in eithertobacco-smokers or non-smokers. A different contribution of the GST genotype to cancer risk may be attributedto a different, as yet undefined, property of the enzymes.     

Polymorphisms in GSTM1, GSTTI and GSTP1 and nasopharyngeal cancer in the east of China: a case-control study

Aim: The study was performed to assess the potential role of GSTM1, GSTT1 and GSTP1 polymorphisms in the risk of nasopharyngeal cancer in Chinese population. Method: We collected 182 cases undergoing pathologic examination and 366 controls from the affiliated hospital of Medical College of Qingdao University from April 2006 to July 2010. Genotyping was based upon duplex polymerase-chain-reactions with the PCR-CTPP method. Results: More smokers were found in NPC patients than controls, and a higher IgA/VCA+ . Individuals carrying null GSTM1 and GSTT1 had 1.76 and 2.01 fold risk of NPC when compared with non-null genotypes, respectively. A non-significant increase risk of NPC was found in individuals with 1b/1b genotype when compared with 1a/1a genotype (OR=1.32, 95%CI=0.60-2.94). When compared with non-null GSTM1 and GSTT1 genotypes, the combination of null/null GSTM1 and GSTT1 genotypes showed moderate increased risk of NPC (OR=3.03, 95% CI=1.74-5.08). Conclusion: Our study provides evidence that genetic deletion of GSTM1 and GSTT1 may contribute to increased susceptibility to NPC in Chinese population, while GSTP1 may not. Our findings provide information relevant to the prevention of NPC.     

Genetic Polymorphism of GSTP1, GSTM1 and GSTT1 Genes and Susceptibility to Chronic Myeloid Leukaemia

Background: The development of cancer results from an imbalance between exposure to carcinogens and the capacity of various enzyme systems engaged in activation or in the detoxification of xenobiotics. The aim of the present study is to investigate the association of GSTP1, GSTM1 and GSTT1 gene polymorphisms in susceptibility to Chronic Myeloid Leukaemia (CML). Methods: A total of 200 CML patients and 100 controls were enrolled in a case-control study with GSTM1 and GSTT1 analysis with PCR and GSTP1 analysis with PCR-RFLP. Results: The GSTT1 null genotype was significantly higher among CML patients suggesting that this genotype is associated with an increased risk of CML. It was found in 42% of cases as compared with 21% of the controls, (OR =2.78, 95% CI: 1.59 - 4.85; p-value =0.000). The presence of the GSTT1 genotype may thus be considered a protective factor for CML. The frequency of individuals carrying GSTM1 null genotype was slightly higher in the control group but this difference was not statistically significant. The GSTM1 null genotype was present in 35% of control cases and 34% of the CML patients, (OR=0.975, 95%CI: 0.58-1.58;p-value=0.863). Individuals with a combined GSTM1 null/GSTT1null genotype had an estimated 2.85-fold increased risk of CML, but no associated risk between GSTP1 Ile 105 Val polymorphism and CML was found (OR=1.99, 95% CI: 0.40 - 9.32; p-value = 0.417). Conclusions: No association between GSTP1 and GSTM1 with susceptibility to CML was found. GSTT1 genotype may be a protective factor for CML, while the null genotype shows association with developing CML.     

Meta-analysis of the association between GSTM1 and GSTT1 gene polymorphisms and cervical cancer

Aim: We conducted a meta-analysis to analyze the influence of GSTM1 and GSTT1 gene polymorphisms on cervical cancer risk, and explore gene-environment interactions. Methods: Identification of relevant studies was carried out through a search of Medline and the EMbase up to Oct. 2011. All case-control studies that investigated the association between GSTM1 and GSTT1 gene polymorphisms and risk of cervical cancer were included. The pooled odds ratio (OR) was used for analyses of results and the corresponding 95% confidence intervals (CI) were estimated. Results: A total of 21 case-control studies were included in the meta-analysis of GSTM1 (2,378 cases and 2,639 controls) and GSTT1 (1,229 cases and 1,223 controls) genotypes. The overall results showed that the GSTM1 null was related to an increased risk of cervical cancer (OR=1.50, 95% CI=1.21-1.85). Subgroup analysis were performed based on smoking and ethnicity. Our results showed that smokers with null GSTM1 genotype had a moderate increased risk of cervical cancer (OR=1.85, 95% CI=1.07-3.20). For the ethnicity stratification, moderate significantly increased risk of null GSTM1 genotype was found in Chinese (OR=2.12, 95% CI=1.43-3.15) and Indian populations (OR=2.07, 95% CI=1.49-2.88), but no increased risk was noted in others. Conclusion: This meta-analysis provided strong evidence that the GSTM1 genotype is associated with the development of cervical cancer, especially in smokers, and Chinese and Indian populations. However, no association was found for GSTT1 null genotype carriers.