Polymorphisms in Turkish population

CYP1A2, CYP2D6, GSTM1, GSTP1, and GSTT1 gene polymorphisms in patients with bladder cancer in a Turkish population.

Department of Medical Biology and Genetics, Faculty of Medicine, Ondokuz Mayis University, 55139, Samsun, Turkey.

Genetic differences in the metabolism of xenobiotics have recently been suggested as modifiers of individual susceptibility to bladder cancer (BC). The objective of this study was to investigate the relationship between bladder tumor and variants of cytochrome p450 1A2 (CYP1A2) 734 C –> A, cytochrome p450 2D6 (CYP2D6) 1934 G –> A, glutathione S-transferase M1, (GSTM1 null), glutathione S-transferase T1 (GSTT1 null), and glutathione S-transferase P1 (GSTP1) I105 V. We investigated the distribution of these polymorphisms in 135 BC patients and in 128 age and sex-matched cancer-free controls. The polymorphisms were analyzed using polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) assay and the multiplex PCR method. Genotype and allele frequencies and their associations with BC risk, demographic factors, smoking status, and tumor stage were investigated. The prevalence of GSTT1 null genotype in cases was 23%, compared with 7% in the control group (OR = 3.94, 95% CI = 1.70-9.38, P = 0.001). There was no association between the studied polymorphisms of CYP1A2, CYP2D6, GSTM1, and GSTP1 genes and BC. There was an association between smoking status and BC. These data seem to indicate that GSTT1 gene polymorphism may be associated with BC in the Turkish population studied. Further studies will be needed to clarify the role of such variation in determining susceptibility to BC.

Department of Medical Biology and Genetics, Faculty of Medicine, Ondokuz Mayis University, 55139, Samsun, Turkey.

Genetic differences in the metabolism of xenobiotics have recently been suggested as modifiers of individual susceptibility to bladder cancer (BC). The objective of this study was to investigate the relationship between bladder tumor and variants of cytochrome p450 1A2 (CYP1A2) 734 C –> A, cytochrome p450 2D6 (CYP2D6) 1934 G –> A, glutathione S-transferase M1, (GSTM1 null), glutathione S-transferase T1 (GSTT1 null), and glutathione S-transferase P1 (GSTP1) I105 V. We investigated the distribution of these polymorphisms in 135 BC patients and in 128 age and sex-matched cancer-free controls. The polymorphisms were analyzed using polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) assay and the multiplex PCR method. Genotype and allele frequencies and their associations with BC risk, demographic factors, smoking status, and tumor stage were investigated. The prevalence of GSTT1 null genotype in cases was 23%, compared with 7% in the control group (OR = 3.94, 95% CI = 1.70-9.38, P = 0.001). There was no association between the studied polymorphisms of CYP1A2, CYP2D6, GSTM1, and GSTP1 genes and BC. There was an association between smoking status and BC. These data seem to indicate that GSTT1 gene polymorphism may be associated with BC in the Turkish population studied. Further studies will be needed to clarify the role of such variation in determining susceptibility to BC.

Department of Medical Biology and Genetics, Faculty of Medicine, Ondokuz Mayis University, 55139, Samsun, Turkey.

Genetic differences in the metabolism of xenobiotics have recently been suggested as modifiers of individual susceptibility to bladder cancer (BC). The objective of this study was to investigate the relationship between bladder tumor and variants of cytochrome p450 1A2 (CYP1A2) 734 C –> A, cytochrome p450 2D6 (CYP2D6) 1934 G –> A, glutathione S-transferase M1, (GSTM1 null), glutathione S-transferase T1 (GSTT1 null), and glutathione S-transferase P1 (GSTP1) I105 V. We investigated the distribution of these polymorphisms in 135 BC patients and in 128 age and sex-matched cancer-free controls. The polymorphisms were analyzed using polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) assay and the multiplex PCR method. Genotype and allele frequencies and their associations with BC risk, demographic factors, smoking status, and tumor stage were investigated. The prevalence of GSTT1 null genotype in cases was 23%, compared with 7% in the control group (OR = 3.94, 95% CI = 1.70-9.38, P = 0.001). There was no association between the studied polymorphisms of CYP1A2, CYP2D6, GSTM1, and GSTP1 genes and BC. There was an association between smoking status and BC. These data seem to indicate that GSTT1 gene polymorphism may be associated with BC in the Turkish population studied. Further studies will be needed to clarify the role of such variation in determining susceptibility to BC.

Department of Molecular Biology and Genetics, Faculty of Science, Bilkent University, Ankara, Turkey.

We investigated the effect of the GSTM1 and GSTT1 null genotypes, and GSTP1 313 A/G polymorphism on bladder cancer susceptibility in a case control study of 121 bladder cancer patients, and 121 age- and sex-matched controls of the Turkish population. The adjusted odds ratio for age, sex, and smoking status is 1.94 [95% confidence intervals (CI) 1.15-3.26] for the GSTM1 null genotype, and 1.75 (95% CT 1.03-2.99) for the GSTP1 313 A/G or G/G genotypes. GSTT1 was shown not to be associated with bladder cancer. Combination of the two high-risk genotypes. GSTM1 null and GSTP1 313 A/G or G/G, revealed that the risk increases to 3.91-fold (95% CI 1.88-8.13) compared with the combination of the low-risk genotypes of these loci. In individuals with the combined risk factors of cigarette smoking and the GSTM1 null genotype, the risk of bladder cancer is 2.81 times (95% CI 1.23-6.35) that of persons who both carry the GSTM1-present genotype and do not smoke. Similarly, the risk is 2.38-fold (95% CI 1.12-4.95) for the combined GSTP1 313 A/G and G/ G genotypes and smoking. These findings support the role for the GSTM1 null and the GSTP1 313 AG or GG genotypes in the development of bladder cancer. Furthermore, gene-gene (GSTM1-GSTP1) and gene-environment (GSTM1-smoking, GSTP1-smoking) interactions increase this risk substantially.