Objective

Loss of genetic diversity leaves a species less able to adapt to new stressors and, therefore, loss of population genetic diversity can foreshadow species loss, with a resultant loss of biological diversity within the community.

The aim of this project was to use deoxyribonucleic acid (DNA) fingerprint techniques as genetic diversity measures for aquatic and terrestrial populations of both animals and plants which inhabit contaminated and/or ecologically sensitive areas impacted by military installations and activities.

Technical Approach

Several fingerprinting methods are applied to population analysis. The first is the variable number of tandem repeats (VNTR) method which is based on Southern blots. The second fingerprinting method is a polymerase chain reaction (PCR) based technique. In this method, bands are produced by preferential amplification of segments of DNA that happen to be bracketed by sequences complementary to the synthetic DNA oligomers used as primers in the reaction. This is termed the DNA amplification fingerprint, or DAF. Additional methods are under development, including use of mini-satellite DNA probes. These methods have been applied to test samples of DNA purified from more than 70 individual brown bullhead catfish representing three populations from both polluted and clean areas. Preliminary data are supportive of the proposed hypothesis, namely that fish from the most polluted aquatic environments are more genetically homogeneous than those from a cleaner environment. Using the raw fingerprint data from these methods, several mathematical treatments for assessing DNA fingerprint diversity were examined and compared in order to determine the best statistically valid approach. The VNTR method also was used to examine genetic variation in the common cattail, Typha latifolia, and the swamp dewberry, Rubus hispidus.

Results

Quantitative measures of population genetic diversity can serve as an assessment tool to identify vulnerable populations/sub-populations of many species of animals and plants, and to monitor their responses to ongoing conservation and protection efforts. The project performed genetic diversity analyses of fish and plants from several sites at Wurtsmith Air Force Base in Michigan and refined statistical evaluation of DNA fingerprints and modification of genetic diversity databases for application to geographic information systems. This work will allow future investigators to examine correlations of genetic diversity with other indicators over geographic scales using relational databases. The project was completed in FY 1997.

Benefits

The project provided (1) baseline data to assess the ecological impact of military activities and (2) a quantitative means to document the ecological state of the impacted area and to prove or disprove cause-effect relationships between munitions byproducts contamination resulting from military activities and ecological effects.