Effect of Pollution on Genetic Diversity in the Southern California Bight

<p>Two intertidal invertebrate species, <em>M galloprovincialis</em> and <em>Balanus glandula</em>, were collected from seven different bay sites along the Southern California coast to test if environmental contamination is associated with the decrease of genetic diversity at the population level. Collections were made at three relatively pristine "clean" sites and four "impacted" sites which were exposed to heavy industrial or boating activity and which had previously, been identified as having measurable levels of pollution. The "Comet" assay (Single Cell Gel electrophoresis) was performed to measure single-strand DNA breaks in mussels at several of the sites in order to confirm differing impacts of pollution on the animals at the different sites. In this assay, cells in impacted populations with increased DNA damage displayed increased migration from the nuclear region towards the anode during electrophoresis. Genetic diversity at the different sites was assessed by comparing fragment polymorphisms generated from genomic DNA by RAPD-PCR (Randomly Amplified Polymorphic DNA - Polymerase Chain Reaction). All populations exhibited a large amount of genetic diversity and were genetically similar to each other. However, several different measures of diversity indicated that for most primers, the populations of both species from impacted sites had lower genetic diversity compared to populations from clean sites. Individuals at impacted sites were more likely to share the same haplotypes than were those from clean sites. Few bands seen in the clean populations were absent from the impacted populations or vice versa, but a number of bands which were common in the clean site populations were significantly less common in the impacted populations. Together, these results suggest that pollution at the impacted sites may act as a selection force decreasing genetic diversity among the resident invertebrate populations.</p>

Name thesis:degree_name

Doctor of Philosophy (PhD)

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Biology

Year

1999

Author dc:creator

• Ma, Xiao Li

Contributors dc:contributor

• David L. Cowles
• Leonard Brand
• Ronald L. Carter
• E. Clifford Herrmann
• George T. Javor

• Marine Biology
• Variation (Biology) -- Effect of pollution on -- Southern California Bight (Calif. and Mexico); Mytilus galloprovincialis -- Effect of pollution on; Balanidae -- Effect of pollution on; ntertidal ecology -- Southern California Bight (Calif. and Mexico).

Statement dc:rights

• This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights.

Language dc:language

English

Repository record dc:identifier

https://scholarsrepository.llu.edu/etd/721

OAI identifier oai:identifier

oai:scholarsrepository.llu.edu:etd-1782