贵州从江侗族威宁彝族、荔波瑶族谷胱甘肽S-转移酶M l、Tl 和Pl 的基因多态性研究

目的：研究贵州从江侗族、威宁彝族、荔波瑶族的GSTs基因多态性。方法：在隔离自然人群中,采用多重等住基因特异聚合酶链反应方法分析GSTM1和GSTT1基因多态性,同时采用PCR-RFLP的方法和TaqMan-MGB探针基因分型方法分析GSTP1（A1578G）基因多态性。结果：贵州从江侗族、成宁彝族、荔波瑶族的GSTM1和GSTT1纯合缺失基因型频率分别为59．6％～71．2％、39．4％～72.5％。其GSTP1（A1578G）基因型频率分别为：野生型（AA）为63.3％～75％、杂合子（AG）为23.2％～35．8％、纯合突变型（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：贵州从江侗族、威宁彝族、荔波瑶族的GSTM1纯合缺失基因型频率在民族间差异无统计学意义,GSTP1（A1578G）基因型频率和等住基因频率在民族间差异无统计学意义,且其等位基因频率均符合Hardy-Weinberg平衡,但其GSTT1纯合缺失基因型频率在民族间差异有统计学意义（P〈0．05）。     

GSTT1 、GSTM1 基因多态性与重度慢性牙周炎 易感性关系的研究

目的：研究GSTTI＋／0和GSTM1＋／0基因型及其联合基因型与重度慢性牙周（chronic pefiodontitis,cp）易感性的关系。方法：用聚合酶链反应检测50例重度慢性牙周炎患者和51例正常对照者的GSIT1＋／0、GSTM1＋／0的基因型。结果：GSTM1（0／0）和GSTT1（0／0）基因型及GSTMI（0／0）与GSTT1（0／0）联合基因型对重度慢性牙周炎相对危险度（OR）分别为9．56（95％CI．3．88—23．59）,8．68（95％CI,3．50—21．51）,36．83（95％CI,10．42—130．13）。结论：在内蒙古汉族人群中,基因型GSTT1（0／0）和GSTM1（0／0）增加了个体对重度慢性牙周炎易感性,且上述两种基因型间存在协同作用。     

中国北方人群谷胱甘肽转硫酶P1基因多态性及其与胃癌遗传易感性的关系

为了分析中国北方人群谷胱甘肽转硫酶P1基因(glutathione-S-transferase P1, GSTP1)多态性分布, 同时探讨GSTP1基因多态性及其与幽门螺杆菌(H. pylori)既往感染联合作用对胃癌发病风险的影响, 采用多聚酶链反应-限制性片段长度多态性(PCR-RFLP)技术检测1,612例外周血DNA GSTP1的多态性; 采用ELISA方法检测血清H. pylori IgG。结果显示, (1) 中国北方人群GSTP1基因Val等位基因分布频率为22%, 胃癌高、低发区GSTP1 Val等位基因分布频率有显著性差异(0.23/0.20); (2) 以Ile/Ile基因型为参照组与其他两种基因型比较进行胃癌的风险分析, 结果显示携带Val/Val基因型的个体患胃癌的危险性最大, 其OR为5.588 (3.256 ~ 9.591); 携带Val等位基因的个体患胃癌危险性是非携带Val等位基因个体的1.587倍; (3) 以H. pylori IgG(-)并携带GSTP1基因纯合野生型(Ile/ Ile)的个体为参照, H. pylori IgG(+)并携带纯合多态基因型(Val/Val)的个体患胃癌的风险最高, OR为17.571(6.207 ~ 49.742)。说明GSTP1 Val等位基因的分布存在人群及地区差异。携带GSTP1 Val等位基因的个体胃癌发病风险增高。GSTP1 Val等位基因纯合型与H. pylori感染对于胃癌的发生具有交互作用。     

支气管哮喘遗传因子研究

研究谷胱甘肽-S-转移酶 （glutathione S-transferase, GST）M1和T1基因多态性与支气管哮喘（asthma bronchial）的关系。采取聚合酶链反应对60名支气管哮喘患者和60名正常对照进行了GSTM1和GSTT1基因非缺失（+）和缺失（0）等位基因分布频率研究。结果表明,与对照组相比,支气管哮喘患者GSTM1基因缺失的纯合子（0/0）频率（81.2%）显著升高（χ2=32.46,P<0.001;wχ2=28.75,P<0.001）。对于GSTT1也得到类似资料。而支气管哮喘患者GSTT1基因缺失等位基因（0/0）频率（71.7%）比对照组（11.7%）显著升高（χ2=26.72,P<0.001;wχ2=35.75,P<0.001）。表明GSTM1、GSTT1缺失等位基因纯合性在哮喘患者中最有特征性的。GSTM1 0/0、GSTT1 0/0结合的频率患者组为61.7%,对照组仅为1.7%（χ2=27.3,P<0.001）。提示GSTM1和GSTT1基因多态性与哮喘有显著性关联,两个基因的突变可以被视为发生支气管哮喘遗传风险因子。     

GSTP1、E-cadherin在垂体腺瘤中的表达及临床意义

目的：研究谷胱甘肽S-转移酶P1（GSTP1）、上皮钙粘蛋白（E-cadherin）在垂体腺瘤中的表达及临床意义。方法：应用免疫组化SP染色法检测30例侵袭性垂体腺瘤与30例非侵袭性垂体腺瘤中GSTP1、E-cadherin的表达。结果：GSTP1在侵袭性垂体腺瘤中的表达较非侵袭性垂体腺瘤显著降低（P〈0.05）;E-cadherin在侵袭性垂体腺瘤中的表达较非侵袭性垂体腺瘤显著降低（P〈0.05）;GSTP1、E-cadherin在垂体腺瘤中的表达呈正相关（r=0.82,P〈0.05）。结论：GSTP1、E-cadherin在垂体腺瘤中的表达与肿瘤侵袭程度显著相关,两者联合检测有助于判断垂体腺瘤侵袭性及预后。     

南京汉族群体肺癌易感性相关基因的研究

为了探讨南京汉族群体肺癌易感性相关基因,我们采用1:1病例对照研究方法,以PCR—RFLP技术检测了152对肺癌和健康对照的CYP1A1、CYP2E1、GSTM1、GSTT1、GSTP1、mEH和NQO1基因的基因型并分析其与肺癌的相关性。结果发现携带CYP1A1突变基因型（wt/mt和mt/mt）的个体明显增加患肺鳞癌的风险(OR=2.31,95%CI=1.23-4.36);GSTT1（-）基因型可使肺癌发生的风险增加2.06倍（95%CI=1.30-3.24）;具有NQO1wt/mt与mt/mt基因型者发生肺癌的风险也有所增高（OR=1.66,95CI%=1.01-2.74）; CYP1A1突变基因型与GSTT1缺失基因型、CYP1A1突变基因型与NQO1突变基因型对肺癌的发生存在协同作用,同时具有两种易感基因型的个体更容易发生肺癌。研究结果表明,CYP1A1、GSTT1、NQO1基因可能与南京汉族群体肺癌遗传易感性有关,基因型之间的联合检测更有助于高危人群的筛选。Abstract: To investigate the genes related to lung cancer susceptibility in Nanjing Han population, China, a 1:1 matched case-control study was performed in which 152 hospital controls were matched to the 152 original lung cancer cases. The polymorphisms of CYP1A1, CYP2E1, GSTM1, GSTT1, GSTP1, mEH and NQO1 genes were analyzed by PCR—RFLP assay. The results showed that the heterozygote and mutation homozygote genotypes of CYP1A1 were related to the risk of squamous cell carcinoma (OR=2.31, 95%CI=1.23-4.36). The risk of suffering from lung cancer was increased 2.06-fold in the individuals with GSTT1（-） genotype (95%CI= 1.30-3.24). The genotype of NQO1 wt/mt and mt/mt was found also to be associated with the risk of lung cancer (OR=1.66,95%CI=1.01-2.74). It was shown that there was no difference in the genotype distribution of CYP2E1, GSTM1, GSTP1 or mEH between cases and controls. Furthermore, stratified analysis suggested that the combination of genotypes of both CYP1A1 and GSTT1 enzymes had a synergistic action in risk of lung cancer (OR=3.41, 95%CI =1.77-6.55). Similarly, there was a cooperation between CYP1A1 mutation genotype and NQO1 mutation genotype (OR=2.45, 95%CI=1.13-5.31). This study suggested that CYP1A1, GSTT1 and gene NQO1 polymorphisms might be associated with the susceptibility to lung cancer in Nanjing Han population. Analysis of gene-gene interactions was helpful to identification of susceptible individuals and screening high-risk population to lung cancer.     

云南汉族酒精依赖综合征与COMT遗传多态性的关联研究

目的：研究儿茶酚胺氧位甲基转移酶（COMT）的不同基因型及等位基因频率在云南汉族酒精依赖综合征患者组和健康对照组的分布差异。方法：应用聚合酶链式反应．限制性片段长度多态性分析法,对COMT基因的rs2075507、rs737865、rs4680、rsl65599四个基因位点进行特异性扩增,限制性内切酶酶切分型。结果：上述4个候选基因中,COMT基因rs737865位点C／C基因型频率在健康对照组较酒依赖组高,其基因型分布在两组中有差异,且具有统计学意义（P〈0．05）。其余3个位点统计学分析均无显著性差异（P〉0．05）。单倍型分析：上述四个候选基因构建出12种主要单倍型（每种单倍型在对照组和酒依赖组中的频率至少有一个大于1％）,单倍型A—C—A—A有可能是云南汉族酒精依赖发生的一种危险因子（OR：2．865,P=0．003347）。连锁不平衡分析显示：云南汉族人群中,COMT基因的rs2075507和rs737865之间存在着强连锁（D〉0．8）。结论：在云南汉族人群中,COMT基因rs2075507、rs4680和rs165599位点与酒依赖无关联性,rs737865C／C基因型可能是酒精依赖的保护因子,可能降低嗜酒的发生率。单倍型A-C-A-A有可能是云南汉族酒精依赖发生的一种危险因子。云南汉族人群中,COMT基因的rs2075507和rs737865之间存在着强连锁。     

白细胞介素一IB 基因多态性与胃癌发生的相关性研究

目的：探讨湖南衡阳地区白细胞介素-1B（IL-1B）基因多态性与胃癌的关系。方法：52例胃癌患者癌旁正常胃粘膜组织和55例慢性胃炎患者胃粘膜组织,应用聚合酶链反应-限制性片段长度多态性（PCR-RFLP）分析技术,进行基因型检测,并对C／C、忻进行测序,比较各基因型在胃癌组和胃炎组中的分布差异。结果：IL-1B-31T、IL-1B-511T等位基因和IL-1B-31T/T、IL-1B-511T／T基因型在胃癌组的分布频率高于胃炎组（P〈0．05）,OR值分别为I．97（95％CI=1．15-3．59）、2．52（95％CI=1．45-4．39）和2．71（95％CI=1,10-6．66）、3,33（95％CI=1．14-9．73）。结论：在湖南衡阳地区IL-1B-3lT／T、IL-1B-511T/T基因型与胃癌发病风险相关。     

G蛋白β亚单位C825T基因多态性与原发性高血压的相关性研究

分析大规模日本人群的G蛋白β亚单位基因（GNB3,C825T-Gprotein β3 subunit C825T）多态性与原发性高血压病（essential hypertension,EH）的关系。采集日本同一个地区健康体检人群为研究对象,共4,830例,其中高血压组（HT：2,092例）,正常血压组（NT：2,738例）。对体检对象做：体重指数（BMI）、吸烟,饮酒等环境因素和血浆胆固醇、甘油三酯等血液生化指标的测量。并用Taqman—PCR化学分析方法对GNB3基因的C825T多态性进行分型检测。GNB3基因的C825T多态性符合Hardy—Weinberg平衡遗传规律。在HT与NT之间,CC、CT、TT遗传表型的频率为NT：24．8％,47．8％和27．4％;HT：22．9％,51．7％和25．4％。C等位基因频率分别为NT：48．72％及HT：48．78％;C825T基因型在HT及NT组之间有显著性差异,基因型频率CC／CT＋TT：P=0．027;OR：1．169;CI95％：1．019～1．341;等位基因频率在两组之间也有统计学差异。C,T：P=0．001;OR：1．154;CI95％：1．064—1．252。CT＋TT基因型携带者发生EH病的危险性为CC基因型携带者的1．169倍（OR）。GNB3基因的C825T的T等位基因EH发病危险是C的1．154倍。GNB3的C825T基因多态性可能是日本人群EH的一个候选基因。     

E选择素基因多态性与新疆哈萨克族患者脑梗死的关系

目的：探讨E一选择素（E-selectin）基因多态性与新疆哈萨克族患者脑梗死（cebreral infarction,CI）的关系。方法：采用聚合酶链反应一限制性片段长度多态性（polymerase chain reaction-restriction fragment length polymorphism,PCR-RFLP）和DNA序列测定法检测103例CI及110例对照组E-selectin基因第4外显子A561C（S128R）、第10外显子C1839T（L554F）多态性。结果：E-se-lectin基因S128R基因型频率和等位基因频率在CI组和对照组比较差异有显著性（P〈0.05）,基因型频率的相对风险分析发现,SR基因型携带者患CI的风险是SS基因型的2.355倍（OR=2.355,95%CI：1.209～4.588）;E-selectin L554F基因型在两组中的分布差异有显著性（X2=5.463,P〈0.05）,基因型频率的相对风险分析,LF基因型患CI的风险是LL基因型的2.315倍（OR=2.315,95%CI：1.132～4.737）。结论：E-selectin S128R和L554F多态性与脑梗死易感性有关;R等位基因和F等位基因可能是新疆哈萨克族CI发病的遗传易感基因。     

Glutathione S-transferase M1, T1, and P1 genotypes and breast cancer risk: a study in a Portuguese population

Glutathione S-transferases are a superfamily of multifunctional enzymes that play a key role in Phase II metabolism, detoxifying therapeutic drugs, and various carcinogens by conjugation with glutathione. We undertook a case-control study in Central-Eastern Portuguese population to evaluate the association of null genotype in GSTM1 and GSTT1 along with the polymorphism in GSTP1 (A/G) and susceptibility to breast cancer. The population sample consisted of 85 patients with histological diagnosis of breast cancer and 102 healthy women. Genomic DNA was extracted from blood samples, and genotyping analyses were performed by PCR-based methods. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated by unconditional logistic regression. We found a increased breast cancer risk associated with GSTM1 null genotype (OR = 3.597; 95% CI = 1.849-6.999; P = 0.0001) and GSTT1 (OR = 2.592; 95% CI = 1.432-4.690; P = 0.002), but the presence of valine alleles compared to isoleucine alleles in codon 105 in GSTP1 did not increase the risk of breast cancer development. The two-way combination of GSTM1 and GTTT1 null genotypes resulted in 8-fold increase for breast cancer risk (OR = 8.287; 95% CI = 3.124-21.980; P = 0.0001) and the three-way combination of GSTP1 105AA/AG and null genotypes for both GSTM1 and GSTT1 resulted in 5-fold increase for breast cancer risk (OR = 5.040; 95% CI = 1.392-18.248; P = 0.016). Our results suggest that GSTM1 and GSTT1 null genotype alone, both combined or combined with GSTP1 valine alleles, are associated with higher susceptibility to breast cancer development.     

Association of glutathione S-transferase gene polymorphisms (GSTM1 and GSTT1) of vitiligo in Korean population

Vitiligo is an acquired pigmentary disorder of the skin involving melanocyte dysfunction. It has been reported that melanocyte impairment could be related to increased oxidative stress. The glutathione S-transferases (GSTs) are group of polymorphic enzymes that are important in protection against oxidative stress. To find the relationship between GSTM1 and GSTT1 polymorphisms with vitiligo susceptibility, GSTM1 and GSTT1 (homozygous deletion vs. non-deleted) polymorphisms between vitiligo patients (n=310) and healthy controls (n=549) were analyzed. We observed significant association in null alleles of the GSTM1 (P<0.001, OR=2.048, 95% CI=1.529-2.743). GSTM1 null type was also statistically different between two vitiligo subtypes and controls (Focal P<0.001, OR=2.224, 95% CI=1.499-3.298; Generalized P=0.001, OR=1.974, 95% CI=1.342-2.904). However, no significant association in GSTT1 (P=0.869, OR=1.024, 95% CI=0.775-1.353) was observed with vitiligo. In combined analysis of GSTM1 and GSTT1, both null type and GSTM1/GSTT1 (null/present) group showed significant differences between controls and vitiligo patients. These results suggest that GSTM1 null type might be associated with vitiligo susceptibility in Korean population.     

Glutathione S-transferase M1, T1 and P1 genetic polymorphisms, cigarette smoking and gastric cancer risk

Glutathione S-transferases (GSTs) belong to a superfamily of detoxification enzymes that provide critical defences against a large variety of chemical carcinogens and environmental toxicants. GSTs are present in most epithelial tissues of the human gastrointestinal tract. We investigated associations between genetic variability in specific GST genes (GSTM1, GSTT1 and GSTP1), the interaction with cigarette smoking and susceptibility to gastric cancer. The GSTM1, GSTT1 and GSTP1 polymorphisms were determined using real-time polymerase chain reaction (PCR) and fluorescence resonance energy transfer with Light Cycler Instrument. The study included 70 patients with gastric cancer and 204 controls. Associations between specific genotypes and the development of gastric cancer were examined by use of logistic regression to calculate odds ratios (OR) and 95% confidence intervals (CI). The GSTM1 homozygous null genotype was associated with an increased risk of developing gastric cancer (OR = 1.73; 95% CI = 1.10-3.04). GSTT1 homozygous null genotype and GSTP1 genotypes were not associated with the risk of gastric cancer. Also there was no difference between cases and controls in the frequency of val-105 and ile-105 alleles (p = 0.07). After grouping according to smoking status, GSTM1 null genotype was associated with an increased gastric cancer risk for smokers (OR = 2.15; 95% CI, 1.02-4.52). There were no significant differences in the distributions of any of the other GST gene combinations. Our findings suggest that the GSTM1 null genotype may be associated with an increased susceptibility to gastric cancer.     

GSTT1 null genotype contributes to coronary heart disease risk: a meta-analysis

Many studies have investigated the association between glutathione S-transferase T1 (GSTT1) null genotype and risk of coronary heart disease (CHD), but the impact of GSTT1 null genotype on CHD is still unclear owing to the obvious inconsistence among those studies. This study aims to quantify the strength of association between GSTT1 null genotype and risk of CHD. We searched the PubMed, Embase and Wangfang databases for studies relating the association between GSTT1 null genotype and risk of CHD. We estimated summary odds ratio (OR) with their 95 % confidence interval (95 % CI) to assess the association. 24 case-control studies with 13, 884 CHD cases and 30, 719 controls were included into this meta-analysis. Meta-analysis of total 24 studies showed GSTT1 null genotype was not associated risk of CHD (random-effects OR = 1.17, 95 % CI 0.97-1.42, P = 0.101). After adjustment for heterogeneity, meta-analysis showed GSTT1 null genotype was associated increased risk of CHD both in total population and Caucasians (for total population, fixed-effects OR = 1.12, 95 % CI 1.05-1.21, P = 0.001; for Caucasians, fixed-effects OR = 1.10, 95 % CI 1.02-1.19, P = 0.010). There was no significant association in the other populations. No evidence of publication bias was observed. Meta-analyses of available data suggest the GSTT1 null genotype contributes to increased risk of CHD in Caucasians.     

GST genotypes and lung cancer susceptibility in Asian populations with indoor air pollution exposures: a meta-analysis

About half of the world's population is exposed to smoke from heating or cooking with coal, wood, or biomass. These exposures, and fumes from cooking oil use, have been associated with increased lung cancer risk. Glutathione S-transferases play an important role in the detoxification of a wide range of human carcinogens in these exposures. Functional polymorphisms have been identified in the GSTM1, GSTT1, and GSTP1 genes, which may alter the risk of lung cancer among individuals exposed to coal, wood, and biomass smoke, and cooking oil fumes. We performed a meta-analysis of 6 published studies (912 cases; 1063 controls) from regions in Asia where indoor air pollution makes a substantial contribution to lung cancer risk, and evaluated the association between the GSTM1 null, GSTT1 null, and GSTP1 105Val polymorphisms and lung cancer risk. Using a random effects model, we found that carriers of the GSTM1 null genotype had a borderline significant increased lung cancer risk (odds ratio (OR), 1.31; 95% confidence interval (CI), 0.95-1.79; p=0.10), which was particularly evident in the summary risk estimate for the four studies carried out in regions of Asia that use coal for heating and cooking (OR, 1.64; 95% CI, 1.25-2.14; p=0.0003). The GSTT1 null genotype was also associated with an increased lung cancer risk (OR, 1.49; 95% CI, 1.17-1.89; p=0.001), but no association was observed for the GSTP1 105Val allele. Previous meta- and pooled-analyses suggest at most a small association between the GSTM1 null genotype and lung cancer risk in populations where the vast majority of lung cancer is attributed to tobacco, and where indoor air pollution from domestic heating and cooking is much less than in developing Asian countries. Our results suggest that the GSTM1 null genotype may be associated with a more substantial risk of lung cancer in populations with coal exposure.     

Association of genetic polymorphisms in glutathione S-transferases and susceptibility to head and neck cancer

Polymorphism in glutathione S-transferase (GST) genes (GSTM1, GSTT1 and GSTP1) and interaction with environmental factors such as tobacco (smoking or chewing) and alcohol on susceptibility to head and neck squamous cell carcinoma (HNSCC) was studied in a case-control study. The study group consisted of 175 patients suffering from HNSCC and 200 age matched healthy controls. Statistical analysis showed an increase in risk to HNSCC in the patients with null genotype of GSTM1 (OR: 2.02; 95% CI: 1.32-3.10; P=0.001) or GSTT1 (OR: 1.66; 95% CI: 1.02-2.69; P=0.04), though the risk was not found to be significant when adjusted for age, sex, smoking, tobacco chewing or alcohol use by multivariate logistic regression model. Our data further showed that combination of deletion genotypes of GST (GSTM1 and GSTT1) confer an even higher risk of HNSCC. Interestingly, GSTP1 wild type genotype in combination with GSTM1 null or GSTT1 null genotype increased susceptibility for HNSCC (OR: 2.49 and 2.75, respectively). Likewise a much greater risk for HNSCC was observed in the patients carrying a genotype combination of GSTM1 null, GSTT1 null and GSTP1 (Ile/Ile) (OR: 4.47; 95% CI: 1.62-12.31; P=0.002). Our data have further provided evidence that tobacco chewing and alcohol consumption are the important risk factors for HNSCC. The interaction between tobacco chewing and null genotype of GSTM1 or GSTT1 resulted in about 3.5- and 2.2-fold increase in the risk respectively in the patients when compared to those not chewing tobacco. Alcohol use resulted in more than 4-fold increase in the risk in the patients with null genotype of GSTM1 as compared to those who are non-drinkers. Alcohol consumption also increased the risk (approx. 3-fold) in the cases with null genotype of GSTT1, though the association was not found to be significant when compared to non-drinkers. Our data have provided evidence that GST polymorphism modifies the susceptibility to HNSCC and have further demonstrated importance of gene-environment interaction in modulating the risk to HNSCC.     

Glutathione S transferase M1 andT1 genotypes and susceptibility to smoking related larynx cancer

Susceptibility to smoking related larynx cancer has been suggested to be associated with genetically determined differences in the ability to detoxify carcinogens present in tobacco smoke. The genetic polymorphisms of glutathione S-transferases, involved in the metabolic inactivation of, for example, tobacco derived carcinogens, have been recognized as potential risk modifiers in various environmentally induced malignancies, including larynx cancer. We employed PCR-based methods to determine the distribution of the GSTM 1 and G STT1 null genotypes in 171 larynx cancer patients and 180 controls to examine further their potential role in individual susceptibility to this neoplasm. The GSTM 1 null genotype was found in 49 1 % of the cases and 57 7 % of the controls and the GSTT1 null genotype in 17 5 % of the cases and 21 7 % of the controls, respectively. Larynx cancer risk associated with the lack of GST M 1 (OR = 0 7; 95 % CI: 0 5-1 1) or GSTT1 (OR = 0 8; 95 % CI: 0 5-1 3) was not significantly affected by age, smoking status, or cancer progression. Although this study thus suggests no role for the G STM 1 and GSTT1 gene polymorphisms in individual susceptibility to smoking-related larynx cancer, due to its relatively small sample size more data are required before any definite conclusions can be drawn.     

The role of GSTM1, GSTT1, GSTP1, and OGG1 polymorphisms in type 2 diabetes mellitus risk: a case-control study in a Turkish population

The aim of the present study was to investigate the role of some polymorphisms in GSTs (GSTM1, GSTT1 and GSTP1) which are very important protective mechanisms against oxidative stress and in OGG1 gene which is important in DNA repair, against the risk of type 2 diabetes mellitus (T2DM). 127 T2DM and 127 control subjects were included in the study. DNA was extracted from whole blood. Analyses of GSTM1 and GSTT1 gene polymorphisms were performed by allele specific PCR and those of GSTP1 Ile105Val and OGG1 Ser326Cys by PCR-RFLP. Our data showed that GSTM1 null genotype frequency had a 2-6 times statistically significant increase in a patient group (OR=3.841, 95% CI=2.280-6.469, p<0.001) but no significance with GSTT1 null/positive and GSTP1 Ile105Val genotypes was observed. When T2DM patients with OGG1 Ser326Cys polymorphism were compared with patients with a wild genotype, a 2-3 times statistically significant increase has been observed (OR 1.858, 95% CI=1.099-3.141, p=0.021). The combined effect of GSTM1 null and OGG1 variant genotype frequencies has shown to be statistically significant. Similarly, the risk of T2DM was statistically increased with GSTM1 null (OR=3.841, 95% CI=2.28-6.469), GSTT1 null+GSTP1 (H+M) (OR=4.118, 95% CI=1.327-12.778) and GSTM1 null+OGG1 (H+M) (OR=3.322, 95% CI=1.898-5.816) and GSTT1 null+OGG1 (H+M) (OR=2.179, 95% CI=1.083-4.386) as compared to the control group. According to our study results, it has been observed that the combined evaluation of GSTM1-GSTT1-GSTP1 and OGG1 Ser326Cys gene polymorphisms can be used as candidate genes in the etiology of T2DM, especially in the development of T2DM.     

Relation of glutathione S-transferase T1, M1 and P1 genotypes and breast cancer risk

The aim of this study was to investigate associations between genetic variability in specific Glutathione S-transferases (GST) genes (GSTM1, GSTT1 and GSTP1) and susceptibility to breast cancer. Genotypes of blood specimen DNA were determined for 65 women with incident cases of breast cancer and 108 control subjects. Associations between specific genotypes and the development of breast cancer were examined by the use of logistic regression to calculate odds ratios (ORs) and 95% confidence intervals (CIs). Neither GSTT1 nor GSTM1 homozygous null genotype was associated with a significant increased risk of developing breast cancer. The presence of valine alleles compared to isoleucine alleles in codon 105 in GSTP1 did not increase the risk of breast cancer development. The risk of breast cancer associated with a combined GSTT1 and GSTM1 null genotype was 3.37 (95% CI = 0.76-2.95, p = 0.115). The only significant association between increased risk of breast cancer development and GSTs polymorphisms was found when GSTT1 null, GSTM1 null and the presence of valine in GSTP1 in codon 105 were combined (p < 0.048, OR = 3.75, 95% CI = 1.01-13.90). Our findings suggest that combined genetic variability in members of the GST gene family may be associated with an increased susceptibility to breast cancer.     

Glutathione S-transferase T1 polymorphism is associated with breast cancer susceptibility

The association between present/null polymorphism of glutathione S-transferase T1 (GSTT1) and breast cancer risk are still inconclusive. We performed a meta-analysis to derive a more precise estimation of the relationship. A total of 48 studies including 17,254 cases and 21,163 controls were involved in this meta-analysis. When all studies were pooled into the meta-analysis, significantly elevated breast cancer risk was associated with null genotype (OR = 1.138, 95% CI = 1.051–1.232). When stratified by ethnicity, significantly increased risks were found for Caucasians (OR = 1.185, 95% CI = 1.075–1.306), but no statistically significantly increased risks were found in Asians (OR = 1.017, 95% CI = 0.846–1.223) and Africans (OR = 1.160, 95% CI = 0.815–1.650). In the subgroup analysis by controls source, statistically significantly elevated risks were both found in population-based studies (OR = 1.123, 95% CI = 1.014–1.243) and hospital-based studies (OR = 1.181, 95% CI = 1.056–1.321). When stratified by menopausal status, no statistically significantly increased risks were found in premenopausal women (OR = 1.115, 95% CI = 0.925–1.345) and postmenopausal women (OR = 1.077, 95% CI = 0.992–1.169). In summary, this meta-analysis suggests that the GSTT1 null genotype is a risk allele for breast cancer development. However, large sample and representative population-based studies with homogeneous breast cancer patients and well matched controls are warranted to confirm this finding.