Enzyme genotype and exposure tolerance in fathead minnow populations acutely and chronically exposed to fluoranthene

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:372524

Diamond, S; Oris, J T; Guttman, S I ^[1]

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1. Miami Univ., Oxford, OH (United States). Dept. of Zoology

Populations residing in contaminated areas often exhibit enhanced genetically based tolerance. Shifts in enzyme genotype frequencies have been suggested as indicators of these adaptive responses. However, the between extant tolerance and enzyme genotype frequencies in affected populations has not been previously reported. The authors report here on attempts, involving acute and chronic exposures, to select for tolerance in populations of fathead minnows. Offspring of survivors of an acutely exposed population were significantly less tolerant relative to naive fish, whereas offspring of fish exposed to a sub-lethal concentration were significantly more tolerant of exposure. Relationships between differential response in the acute exposure were elucidated using failure-time methods. Genotype at one focus, glucose phosphate isomerase (GPI), was significantly related to survival time during this exposure. In addition, significant differences in GPI allele frequency between survivors and their offspring were also apparent. Comparison of offspring of chronically exposed fish with offspring of unexposed fish indicated a significant shift in allele frequencies at the GPI locus. These F1 populations were also exposed acutely to fluoranthene to assess their relative tolerance. Separate failure-time analyses for these populations again indicated a significant relationship between GPI genotype and mortality in the control fish (and at three other loci), but not in the exposure fish. Overall, five loci were significantly related to mortality in the control population, whereas one locus was related to mortality in the exposure offspring. These results suggest that enzyme genotype frequencies can be consistent indicators of population response to exposure and that selection by contaminants may reduce variability in these relationships.

• OSTI ID: 372524
• Report Number(s): CONF-9511137--; ISBN 1-880611-03-1
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
56 BIOLOGY AND MEDICINE
APPLIED STUDIES
BIOLOGICAL INDICATORS
BIOLOGICAL MARKERS
CONDENSED AROMATICS
FATHEAD MINNOW
GENE MUTATIONS
GENETIC EFFECTS
GENETIC VARIABILITY
ISOMERASES
TOLERANCE
WATER POLLUTION