Ethnic distribution of the glutathione transferase Mu 1-1 (GSTM1) null genotype in 1473 individuals and application to bladder cancer susceptibifity

Polycyclic aromatic hydrocarbons, found in cigarette smoke, food and industrial materials, are potential human carcinogens. Deficiency of detoxifying enzymes, such as glutathione transferases, may affect the metabolic fates of these chemicals and raise cancer risks in exposed individuals. The GSTM1 null genotype is a common form of glutathione transferase deficiency. Because knowledge of its ethnic distribution would be useful in epidemiologic studies, we measured the frequencies of the GSTM1 null genotype among healthy blacks, whites, Asian Indians, Chinese, Japanese, Koreans, Filipinos, Samoans and Hispanics. Rapid genotyping was done by use of a PCR assay, with dried blood spots on blotter paper as DNA templates