Chromosome Aberrations and DNA Strand Breaks in Glaucous Gull (Larus Hyperboreus) Chicks Fed Environmentally Contaminated Gull Eggs

Abstract

In this present laboratory study, our results suggest that a complex mixture of pollutants found in the marine environment exerts genotoxic effects on glaucous gull (Larus hyperboreus) chicks fed environmentally contaminated gull eggs. Chromosome aberrations, quantified by cytogenetic analysis of blood cells, and DNA strand breaks, quantified by agarose gel electrophoresis and image data analysis, were determined in glaucous gull chicks fed environmentally contaminated gull eggs (exposed group) and in chicks fed hen eggs (control group). For both female and male gulls, the fraction of damaged metaphases was quantitatively higher in exposed than in control groups. On the other hand, the differences between the control and the exposed groups were more relevant when the chromosomal aberration data were treated as group totals rather than at the individual level. Consistent results were obtained in the DNA strand break analyses. The control group appeared to display a greater median molecular length (MML) than the exposed group.

This study is part of a larger project, “Genotoxic Effects in Glaucous Gull (Larus hyperboreus),” which also is coordinated with the project “The Effects of Persistent Organic Pollutants (POPs) on Glaucous Gull (Larus hyperboreus): An Integrated Study,” financed by the Transport and Effects Programs administered by the Norwegian Polar Institute. Financial support was also obtained by the Norwegian University of Science and Technology via the Research Council of Norway's Strategic University Program “Basic Pollution Research” (project 110686/420). Kjetil Sagerup, the Norwegian Polar Institute, was responsible for setting up and conducting the field laboratory experiment in Ny-Ålesund. Experimental animals were treated in accordance with national and institutional guidelines for animal welfare.

Notes

^a Mitotic index: the fraction of dividing cells per 1000.

^a Chromosomes 3, 6, and 12 are telocentric.

^b Note that chromosome 7 is the Z and chromosome 11 is the W.

^a Mitotic index: the fraction of dividing cells per 1000.

Villa, R. A. 2004. Persistent organic pollutants in eggs of glaucous gull from the Barents Sea: Differences related to the laying order. Comparison between eggs and mother's blood. MSc thesis: University of Madrid, Spain.