• 제목/요약/키워드: null genotype

검색결과 65건 처리시간 0.025초

Predictive Role of GSTs on the Prognosis of Breast Cancer Patients with Neoadjuvant Chemotherapy

  • Bai, Yun-Lu;Zhou, Bing;Jing, Xiao-Yue;Zhang, Bin;Huo, Xiao-Qing;Ma, Chao;He, Jian-Miao
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제13권10호
    • /
    • pp.5019-5022
    • /
    • 2012
  • Objective: To evaluate the predictive value of GST gene polymorphisms with regard to prognosis of breast cancer patients receiving neoadjuvant chemotherapy. Methods: A total of 159 patients were included in our study between January 2005 and January 2007. All the patients were followed up until January 2012. Genotyping was based upon the duplex polymerase-chain-reaction with the PCR-CTPP method. Results: Patients with null GSTM1 and GSTP1 Val/Val genotypes had significantly had better response rates to chemotherapy when compared with non-null GSTM1 and GSTP1 Ile/Ile genotypes (OR=1.96 and OR=2.14, respectively). Patients with the GSTM1 null genotype had a longer average survival time and significantly lower risk of death than did those with non-null genotypes (HR=0.66). Similarly, those carrying the GSTP1 Val/Val genotype had 0.54-fold the risk of death of those with GSTP1 Ile/Ile (HR=0.54). Conclusion: A significant association was found between GSTM1 and GSTP1 gene polymorphisms and clinical outcomes in breast cancer cases.

Systematic Analysis on the GSTM1 Null Phenotype and Prostate Cancer Risk in Chinese People

  • Shi, Jing;Zhuang, Yan;Liu, Yan;Yan, Cheng-Quan;Liu, Xian-Kui;Zhang, Ying
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제16권5호
    • /
    • pp.2009-2011
    • /
    • 2015
  • Objective: Glutathione S-transferase M 1 (GSTM1) is implicated as a risk factor for prostate cancer. However, this issue is not clear in Chinese population. This systemic analysis was conducted to evaluate the effect of GSTM1 null genotypes on prostate cancer risk in Chinese. Methods: Published studies investigating the associations between GSTM1 null genotypes and the risk of prostate cancer in China were identified by using a predefined search strategy. Main statisticals were pooled and estimated according to the primarily reported data. Results: The prevalence of the GSTM1 null genotype was higher in prostate cancer patients than in controls, with significance. Conclusion: The GSTM1 null genotypes is associated with increased risk of prostate cancer in Chinese.

Predictive Role of Glutathione-S-transferase Gene Polymorphisms in the Survival of Gastric Cancer Cases

  • Wang, Zhao-Yang;Zhou, Jing;Luo, Li;Huang, Ying-Long;Dong, Pei-De
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제13권4호
    • /
    • pp.1515-1518
    • /
    • 2012
  • Aim: We conducted a prospective study in an Chinese population to detect the association between GSTM, GSTT and GSTP gene polymorphisms and survival of gastric cancer. Methods: A prospective follow-up study with 317 gastric cancer patients was conducted between January 2003 and January 2005. GSTM1, GSTT1 and GSTP1 genotyping was performed using ABI TaqMan Gene Expression assays. Results: Of 317 patients, 5 were lost to follow-up due to migration, while the remaining 302 patients completed the study. The median follow-up time was 34.2 months (range: 2 to 60 months), during which a total of 120 (39.1%) died of gastric cancer. The GSTT1-null genotype showed a significant increased risk of death from gastric cancer, with an HR (95% CI) of 1.59 (1.04-3.58). Moreover, we found individuals carrying null-GSTM1 and null-GSTT1 had a moderate higher risk of death from gastric cancer, with an HR of 1.92 (1.05-3.65). Conclusion: This study reported the carriage of null GSTT1 and null GSTM1 might be linked to the higher death risk from gastric cancer in Chinese population.

Empirical Statistical Power for Testing Multilocus Genotypic Effects under Unbalanced Designs Using a Gibbs Sampler

  • Lee, Chae-Young
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제25권11호
    • /
    • pp.1511-1514
    • /
    • 2012
  • Epistasis that may explain a large portion of the phenotypic variation for complex economic traits of animals has been ignored in many genetic association studies. A Baysian method was introduced to draw inferences about multilocus genotypic effects based on their marginal posterior distributions by a Gibbs sampler. A simulation study was conducted to provide statistical powers under various unbalanced designs by using this method. Data were simulated by combined designs of number of loci, within genotype variance, and sample size in unbalanced designs with or without null combined genotype cells. Mean empirical statistical power was estimated for testing posterior mean estimate of combined genotype effect. A practical example for obtaining empirical statistical power estimates with a given sample size was provided under unbalanced designs. The empirical statistical powers would be useful for determining an optimal design when interactive associations of multiple loci with complex phenotypes were examined.

Relationship Between GSTT1 Gene Polymorphism and Hepatocellular Carcinoma in Patients from China

  • Chen, Jie;Ma, Liang;Peng, Ning-Fu;Wang, Shi-Jun;Li, Le-Qun
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제13권9호
    • /
    • pp.4417-4421
    • /
    • 2012
  • Objective: The results from studies on associations of the glutathione S-transferase T1 (GSTT1) gene polymorphism and hepatocellular carcinoma (HCC) risk in Chinese populations are still conflicting. This meta-analysis was performed to evaluate the relationship in detail. Methods: Eligible reports were recruited into this meta-analysis from the databases of PubMed, Embase, Cochrane Library and CBM-disc (China Biological Medicine Database). Results were expressed with odds ratios (OR) for dichotomous data, and 95% confidence intervals (CI) were also calculated. Results: Eighteen investigations were identified for the analysis of association between polymorphic deletion of GSTT1 and HCC, consisting of 2,693 patients with HCC and 4,696 controls. Null genotype of GSTT1 was associated with HCC susceptibility in Chinese (OR=1.53, 95%CI: 1.28-1.82; P<0.00001). Conclusion: The GSTT1 null genotype is associated with HCC susceptibility in Chinese.

Glutathione S-transferase M1 and T1 Polymorphisms, Cigarette Smoking and HPV Infection in Precancerous and Cancerous Lesions of the Uterine Cervix

  • Sharma, Anita;Gupta, Sanjay;Sodhani, Pushpa;Singh, Veena;Sehgal, Ashok;Sardana, Sarita;Mehrotra, Ravi;Sharma, Joginder Kumar
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제16권15호
    • /
    • pp.6429-6438
    • /
    • 2015
  • Glutathione S-transferases (GSTs) play an important role in detoxification of carcinogenic electrophiles. The null genotypes in GSTM1 and GSTT1 have been implicated in carcinogenesis. Present study was planned to evaluate the influence of genetic polymorphisms of GSTM1 and GSTT1 gene loci in cervical carcinogenesis. The study was conducted in Lok Nayak hospital, New Delhi. DNA from clinical scrapes of 482 women with minor gynaecologic complaints attending Gynaecology OPD and tumor biopsies of 135 cervical cancer cases attending the cancer clinic was extracted. HPV DNA was detected by standard polymerase chain reaction (PCR) using L1 consensus primer pair. Polymorphisms of GSTM1 and GSTT1 were analysed by multiplex PCR procedures. Differences in proportions were tested using Pearson's Chi-square test with Odds ratio (OR) and 95% confidence interval (CI). The risk of cervical cancer was almost three times in women with GSTM1 homozygous null genotype (OR-2.62, 95%CI, 1.77-3.88; p<0.0001). No association of GSTM1 or GSTT1 homozygous null genotypes was observed in women with normal, precancerous and cervical cancerous lesions among ${\leq}35$ or >35 years of age groups. Smokers with null GSTT1 genotype had a higher risk of cervical cancer as compared to non-smokers (OR-3.01, 95% CI, 1.10-8.23; p=0.03). The results further showed that a significant increased risk of cervical cancer was observed in HPV positive smoker women with GSTT1 (OR-4.36, 95% CI, 1.27-15.03; p=0.02) and GSTM1T1 (OR-3.87, 95% CI, 1.05-14.23; p=0.04) homozygous null genotypes as compared to HPV positive non smokers. The results demonstrate that the GST null genotypes were alone not associated with the development of cervical cancer, but interacted with smoking and HPV to exert effects in our Delhi population.

Mn-SOD와 GST 유전자 다형성에 따른 유아의 산화손상지표의 분포 (Oxidative damage biomarker levels according to Mn-SOD and GST gene polymorphisms in preschool children)

  • 신유경;최지원;오세영;정자용
    • Journal of Nutrition and Health
    • /
    • 제48권6호
    • /
    • pp.468-475
    • /
    • 2015
  • 우리나라 일부 건강한 유아를 대상으로 Mn-SOD Val16Ala, GSTP1 Ile105Val, GSTT1 present/null, GSTM1 present/null 유전자 다형성 분포를 살펴본 결과, Mn-SOD Val/Val형, GSTP1 Ile/Ile형, GSTT1 null 형, GSTM1 null 형이 주된 (major) 유전자형인 것으로 나타났다. 이 중 Mn-SOD Val/Val형은 Val/Ala 또는 Ala/Ala형에 비해 소변 8-OHdG 수준이 유의적이지는 않으나 높은 경향을 나타내었고, GSTP1 Ile/Ile형은 Ile/Val 또는 Val/Val형에 비해 소변 8-OHdG 수준이 유의적으로 낮았다. 간접흡연에의 노출 여부와 간접흡연-유전자 다형성의 상호 작용이 산화손상지표에는 유의적인 영향을 미치지 않는 것으로 나타났다. 이상의 결과로 볼 때 건강한 유아에서 GSTP1 Val allele 보유한 경우 산화적 손상에 대해 취약할 수 있음을 제시하며, 추후 대규모 연구를 통한 검증 및 이들 유전자형을 보유한 대상자를 위한 효과적인 영양 중재방안에 대한 고려가 필요할 것으로 사료된다.

Null Allele in the D18S51 Locus Responsible for False Homozygosities and Discrepancies in Forensic STR Analysis

  • Eom, Yong-Bin
    • 대한의생명과학회지
    • /
    • 제17권2호
    • /
    • pp.151-155
    • /
    • 2011
  • Short tandem repeats (STRs) loci are the genetic markers used for forensic human identity test. With multiplex polymerase chain reaction (PCR) assays, STRs are examined and measured PCR product length relative to sequenced allelic ladders. In the repeat region and the flanking region of the commonly-used STR may have DNA sequence variation. A mismatch due to sequence variation in the DNA template may cause allele drop-out (i.e., a "null" or "silent" allele) when it falls within PCR primer binding sites. The STR markers were co-amplified in a single reaction by using commercial PowerPlex$^{(R)}$ 16 system and AmpFlSTR$^{(R)}$ Identifiler$^{(R)}$ PCR amplification kits. Separation of the PCR products and fluorescence detection were performed by ABI PRISM$^{(R)}$ 3100 Genetic Analyzer with capillary electrophoresis. The GeneMapper$^{TM}$ ID software were used for size calling and analysis of STR profiles. Here, this study described a forensic human identity test in which allelic drop-out occurred in the STR system D18S51. During the course of human identity test, two samples with a homozygous (16, 16 and 21, 21) genotype at D18S51 locus were discovered using the PowerPlex$^{(R)}$ 16 system. The loss of alleles was confirmed when the samples were amplified using AmpFlSTR$^{(R)}$ Identifiler$^{(R)}$ PCR amplification kit and resulted in a heterozygous (16, 20 and 20, 21) genotype at this locus each other. This discrepancy results suggest that appropriate measures should be taken for database comparisons and that allele should be further investigated by sequence analysis and be reported to the forensic community.

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

  • Yamada, Ikuhiro;Matsuyama, Masato;Ozaka, Masato;Inoue, Dai;Muramatsu, Yusuke;Ishii, Hiroshi;Junko, Ueda;Ueno, Makoto;Egawa, Naoto;Nakao, Haruhisa;Mori, Mitsuru;Matsuo, Keitaro;Nishiyama, Takeshi;Ohkawa, Shinichi;Hosono, Satoyo;Wakai, Kenji;Nakamura, Kozue;Tamakoshi, Akiko;Kuruma, Sawako;Nojima, Masanori;Takahashi, Mami;Shimada, Kazuaki;Yagyu, Kiyoko;Kikuchi, Shogo;Lin, Yingsong
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제15권1호
    • /
    • pp.391-395
    • /
    • 2014
  • Background: We aimed to evaluate the role of genetic polymorphisms in tobacco carcinogen-metabolizing genes and their interactions with smoking in a hospital-based case-control study of Japanese subjects. Materials and 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 electrophilic molecules. The study population consisted of 360 patients and 400 control subjects, who were recruited from several 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 genotype was approximately 56% and 48%, respectively. Cases and controls were comparable in terms of GSTM1 and GSTT1 genotype distributions. Neither of the deleted polymorphisms in GSTM1 and GSTT1 was associated with the risk of pancreatic cancer, with an age- and sex-adjusted OR of 0.99 (95%CI: 0.74-1.32) for the GSTM1-null genotype, 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) for individuals 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 results indicate no overall association between the GSTM1 and GSTT1 deletion polymorphisms and pancreatic cancer risk in the Japanese subjects in our study.

Predictive Potential of Glutathione S-Transferase Polymorphisms for Prognosis of Osteosarcoma Patients on Chemotherapy

  • Zhang, Shai-Lin;Mao, Ning-Fang;Sun, Jun-Ying;Shi, Zhi-Cai;Wang, Bing;Sun, Yong-Jian
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제13권6호
    • /
    • pp.2705-2709
    • /
    • 2012
  • Objective: To evaluate the predictive value of glutathione S-transferase (GST) gene polymorphisms for the prognosis of osteosarcoma patients receiving chemotherapy. Methods: A total of 159 patients were included in our study between January 2005 and December 2007., with follow-up until January 2012. Genotyping was based upon the duplex polymerase-chain-reaction with the PCR-CTPP method. Results: At the time of diagnosis, 15.4% of the patients presented with metastasis, while 22.3% developed metastasis during follow-up. At the time of final analysis on January 2012, the median follow-up was 45.5 months. Patients with null GSTM1 and GSTT1 had a higher event free survival rate than non-null genotype, but no significant association was found between the two genotypes and prognosis of osteosarcoma. Individuals with GSTP1 Val/Val genotype tended to live shorter than with the IIe/IIe genotype, and we found a significantly higher risk of death from osteosarcoma (adjusted HR=2.35, 95% CI=1.13-4.85). Conclusion: The GSTP1 gene polymorphism may have an important role in the prognosis of osteosarcoma patients with chemotherapy. Further analyses with larger samples and more genes encoding metabolizing and DNA repair enzymes are warranted.