A new report from the National Research Council recommends that government agencies enhance their efforts to incorporate genomic data into risk assessments of chemicals and medicines, and calls for a concerted effort to fully develop these methods' potential to protect public health.
Chemicals and drugs often cause health problems by altering gene expression and other cell activity, and research on these processes -- called toxicogenomic research -- could eventually lead to more-sensitive toxicity tests that can supplement current tests, the report says. Toxicogenomic tests can also pinpoint individuals with genetic vulnerabilities and help them avoid chemicals or medications that might make them ill.
A major, coordinated effort approaching the scale of the Human Genome Project is needed both to develop these technologies fully and to address the ethical challenges they pose, such as protecting the confidentiality of individuals' genetic information, the report says. As part of this endeavor, which could be called a "human toxicogenomics initiative," a new database is needed to consolidate the massive amounts of data currently being generated by toxicogenomic studies.
"We have just begun to tap the potential for toxicogenomic technologies to improve risk assessment," said David Christiani, chair of the committee that wrote the report, and professor of occupational medicine and epidemiology at the Harvard School of Public Health. "To harvest public health benefits requires both greater investment in research and coordinated leadership."
Toxic substances and drugs can potentially disrupt gene processes within cells, thus disturbing the cells' healthy functioning. In addition, an individual's genetic variations can leave him or her particularly susceptible to the effects of chemicals or side effects of medications. For example, studies have shown that certain inherited gene variations may make some people more prone to symptoms such as nausea and impaired muscle function when exposed to a common pesticide, the report notes.
Using new toxicogenomic technologies, researchers can identify toxic processes as they unfold at an early, molecular stage, long before symptoms appear. This knowledge will support the development of tests that can more accurately predict whether a chemical will be hazardous, and at what dose. The tests' sensitivity also could lead to better prediction and prevention of damage to fetuses at critical stages of development. Finally, toxicogenomic studies can inform individuals about their particular genetic vulnerabilities.
Given the potential of toxicogenomics to reduce and prevent health risks, regulatory agencies should expand their research and enhance efforts to use these methods to aid risk assessments, the report says. It also calls on the National Institute of Environmental Health Sciences and other stakeholders in government, academia, and industry to explore the feasibility of implementing a concerted human toxicogenomics initiative.