SREL DNA Lab
PFGE Introduction

Environmental contaminants can induce effects in wildlife that are destructive to an animal's genetic integrity.  One effect that genotoxic substances may cause is DNA strand breakage.  When both strands of DNA are broken, they may be repaired incorrectly or not at all.  This could result in health problems to an individual (e.g., cancer, reduced fertility), or heritable genetic changes to its offspring.  Thus determining the amount of damage as DNA strand breakage would be a useful indicator, or genetic biomarker, of some forms of environmental contamination.

Non-mammalian vertebrates such as fish, birds, reptiles and amphibians are easier to analyze for strand breakage because their red blood cells are nucleated and contain DNA.  Using DNA from blood is better than from tissue because 1) blood can be collected with minimal stress to the individual, 2) it's easier to manipulate in the lab, and 3) the DNA is less likely to get broken in testing.  

Top-level carnivores like largemouth bass may be more likely to show genetic damage than those at lower trophic levels because some toxicants biomagnify through the food chain.  We therefore planned an experiment on bass to help refine the PFGE technique so it could be used to indicate DNA strand breakage from genotoxicants.