Utilizing Molecular Technologies for Bioindicator Research

Abstract

Endocrine acting compounds dispersed into the environment have been reported to adversely affect growth and reproduction of wildlife. Some of the compounds are industrial by-products, but evidence points to sewage treatment plants as a major source of these contaminants. Typically whole life studies with vertebrates and invertebrates are performed to determine adverse health effects. This approach is ecologically sound, but may not point to the mechanisms by which the contaminants exert their effects. Molecular technologies have the potential to shorten the time of evaluation and provide integrated information to tie changes at the molecular level with adverse health effects. We describe molecular approaches that can be used to determine changes in gene expression patterns elicited by exposure to contaminants. Differential display RT-PCR and microarray analysis are powerful methods to measure the biological effects of exposure to environmental compounds. Both techniques need to be validated by quantitative measurements such as real time quantitative PCR (Q-PCR). These assays are complementary to standard methods of assessing toxicant effects and should lead to quick assessment of molecular mechanisms of toxicity. Many laboratories have started to use molecular biomarkers for their studies and are making the case for their usefulness in risk assessment.

This publication was made possible by grants from NIEHS (#P42 ES 07375, Superfund Program Research Grant, and #1R43 ES013637-01), HBOI grant #2004-13, and EPA (#RD831848). The contents are solely the responsibility of the authors and do not represent the official views of the NIEHS, NIH, or the EPA. Nancy Denslow and Patrick Larkin are equity holders in EcoArray Inc., a company commercializing microarray technology. They may benefit from this technology by receiving royalties and equity growth.

Keywords:

• differential display
• endocrine disruption
• fish
• microarray
• quantitative PCR
• subtractive hybridization

Notes

This publication was made possible by grants from NIEHS (#P42 ES 07375, Superfund Program Research Grant, and #1R43 ES013637-01), HBOI grant #2004-13, and EPA (#RD831848). The contents are solely the responsibility of the authors and do not represent the official views of the NIEHS, NIH, or the EPA. Nancy Denslow and Patrick Larkin are equity holders in EcoArray Inc., a company commercializing microarray technology. They may benefit from this technology by receiving royalties and equity growth.

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