My current research is focused on assessing
the molecular and population genetic effects environmental irradiation has on native and
laboratory rodents. However, I am interested in assessing the genotoxicity of polluted
environments using vertebrates as biological sentinels. The goals of using molecular and
population genetics as tools for assessing environmental genotoxicity are 1) to apply and
understand mechanistic interactions between pollutants and biota, 2) assess and
potentially manage or monitor the risk of polluted environments to wildlife, and 3) assess
and manage or monitor the risk of polluted environments to humans. In other words, if an
area is contaminated, the primary questions to answer include "What is/are the
genetic risk(s) associated with inhabiting or working in that area?" and "What
are the long-term consequences resulting from chronic exposure to environmentally relevant
levels of contamination?". Principally, "How do we detect genetic effects prior
to the incidence of disease?" and essentially use molecular genetics as a predictive,
prospective tool with which to assess the potential risk of any mutagen, mutagenic
environment, or any contaminated environment which adversely affects population genetic
characteristics. The molecular tools I use include mitochondrial DNA, nuclear DNA
repetitive elements, and transgenic systems (Big
BlueŽ Mutagenesis Rodent Assay System). Standard molecular
techniques are employed including PCR, nucleotide sequencing, and several cloning assays
(phage and plasmid-based). Data analyses include population genetics (unique
polymorphisms, genetic diversity) and mutation analysis (mtDNA heteroplasmy, transgenes).
I am also interested in the developing technologies such as gene expression profiling and
microarray (DNA and mRNA) analysis. All of these continue to serve as valuable endpoints
of genotoxicant and toxicant-induced stress ranging from the molecular to the population
level of biological organization.
A uniquely interesting site from which
biological samples are currently taken from is an area approximately 1.5 km WSW of the
Chornobyl Nuclear Power Plant (CNPP) in northern Ukraine. I am working with Dr.
Robert J. Baker, Dr.
Ron K. Chesser, and Dr.
Brenda E. Rodgers. Dr. Baker's expertise is in the field of mammalian
systematics and biology, Dr. Chesser's expertise is in the fields of population genetics
and radiation dosimetry, and Dr. Rodgers' expertise is in the field of cytogenetics.
Several species of rodent inhabit areas contaminated with extremely high levels of
environmental radiation. Long-lived radioisotopes including 137Cesium and 90Strontium
persist in several areas which restrict human activity. The animals and plants in these
areas have incorporated these radioisotopes internally. In fact, one species we have
conducted a considerable amount of research on, the bank vole (Clethrionomys
glareolus), harbors the highest internal burdens of radiocesium ever
documented. In contrast to the nuclear desert typically envisioned, the radioactive
exclusion zone is ecologically vibrant and dynamic. Several species including moose (Alces
alces), gray wolf (Canus lupus),
Russian boar (Sus scrofa), masked dormouse (Dryomys
nitedula), Whooper Swan (Cygnus cygnus),
river otter (Lutra canadensis), red fox (Vulpes
vulpes), raccoon dog (Genus species), Black Stork (Ciconia
nigra), Golden Eagle (Aquila chrysaetos),
and Fish Eagle (Haliaeetus sp.) have been
observed within the exclusion zone and are rarely or never outside where human activity is
not restricted and habitat is primarily used for agriculutural purposes.
Sites of Interest:
Tech University (Department
of Biological Sciences)
Institute of Environmental and Human Health
A&M University (Dr.
John W. Bickham's WWW site)
International Laboratory of Research and Technology (International Radioecology