CS13 Environmental Ecotoxicology
Date: Friday, June 14, 2002
Time: 11:15:00 AM
Location: Esquimalt
 
GarbalenaG, University of Texas at El Paso, El Paso, USA, ggarbalena@utep.edu
Walsh, E, J, University of Texas at El Paso, El Paso, USA, ewalsh@utep.edu
 
ASSESSMENT OF GENETIC DIVERSITY IN FISHES AND ROTIFERS IN THE RIO GRANDE: A BIOMARKER OF ANTHROPOGENIC STRESS
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Environmental contamination can directly or indirectly reduce the genetic diversity of a population. The primary goal of this study is to evaluate the condition of the Rio Grande aquatic ecosystem by determining genetic diversity of its inhabitants at different sites along the river. Fishes and rotifers from three contaminated sites and a fourth relatively clean were sampled. Genetic variation of twenty individuals of two species of fishes (Cyprinis carpio and Dorosoma cepedianum) and rotifers (Plationus patulus and Euchlanis dilatata) was assessed using Amplified Fragment Length Polymorphisms (AFLP). Eight primer combinations were chosen based on their reproducibility and levels of variation for further analyses. GeneImagIR software was used to score and match polymorphisms. The number of different genotypes at each site was determined and Nei's index calculated. The relationship between genetic and linear geographical distances will be analyzed with a Mantel test, while comparisons of levels of genetic variation between sites will be assessed using an Analysis of Molecular Variation (AMOVA). Our results help establish the measure of genetic diversity as a useful biomarker in aquatic systems.