Human germ cell mutagens.

Human genetic disorders constitute a major public health burden in this country and around the world. The possibility that exposures to mutagenic environmental agents may result in induced genetic damage in human germ cells and thereby increase the incidence of genetic disease has been investigated in research laboratories and in epidemiology studies for decades. The capacity of ionizing radiation and some chemicals to induce transmissible genetic damage in the germ cells of laboratory mammals has been clearly demonstrated and extensively investigated. To date, no clear evidence of such effects in humans has been reported although increased frequencies of chromosomal aberrations have been detected in human sperm following exposures to radiation or chemotherapeutic agents. Evolving methods to detect molecular changes in DNA offer to improve our abilities to detect induced genetic changes. The integration of these methods into mutation epidemiology studies promises to help resolve some of the questions regarding human genetic risk.