Genetic polymorphism in three glutathione s-transferase genes and breast cancer risk

Woldegiorgis, S. ; Ahmed, R.C. ; Zhen, Y. ; Erdmann, C.A. ; Russell, M.L. ; Goth-Goldstein, R.

Lawrence Berkeley National Laboratory

关键词: Dna Damages;    Toxins;    Genotype;    Genetics;    Carcinogens;   

DOI  :  10.2172/799602
RP-ID  :  LBNL--50365
RP-ID  :  AC03-76SF00098
RP-ID  :  799602

美国|英语

来源: UNT Digital Library

【 摘 要 】

The role of the glutathione S-transferase (GST) enzyme family is to detoxify environmental toxins and carcinogens and to protect organisms from their adverse effects, including cancer. The genes GSTM1, GSTP1, and GSTT1 code for three GSTs involved in the detoxification of carcinogens, such as polycyclic aromatic hydrocarbons (PAHs) and benzene. In humans, GSTM1 is deleted in about 50% of the population, GSTT1 is absent in about 20%, whereas the GSTP1 gene has a single base polymorphism resulting in an enzyme with reduced activity. Epidemiological studies indicate that GST polymorphisms increase the level of carcinogen-induced DNA damage and several studies have found a correlation of polymorphisms in one of the GST genes and an increased risk for certain cancers. We examined the role of polymorphisms in genes coding for these three GST enzymes in breast cancer. A breast tissue collection consisting of specimens of breast cancer patients and non-cancer controls was analyzed by polymerase chain reaction (PCR) for the presence or absence of the GSTM1 and GSTT1 genes and for GSTP1 single base polymorphism by PCR/RFLP. We found that GSTM1 and GSTT1 deletions occurred more frequently in cases than in controls, and GSTP1 polymorphism was more frequent in controls. The effective detoxifier (putative low-risk) genotype (defined as presence of both GSTM1 and GSTT1 genes and GSTP1 wild type) was less frequent in cases than controls (16% vs. 23%, respectively). The poor detoxifier (putative high-risk) genotype was more frequent in cases than controls. However, the sample size of this study was too small to provide conclusive results.