(full paper is archived in the Miller Library)
Title: Determining the population structure of Gillichthys mirabilis using isozyme electrophoresis and AFLP DNA fingerprinting
Student Author(s): Chen, Emily J.
Faculty Advisor(s): Powers, Dennis
%E Somero, George
%E Villa, Gary
Location: Final Papers Biology 175H
Date: June 1997
Abstract: Gillichthys mirabilis, the longjaw mudsucker, is a Gobiid fish that lives under a wide variety of temperature ranges in bays and estuaries along the Pacific coast of North America. A population genetics study could suggest whether genetic differences associated with differential physiological adaptations have occurred. Samples of Gillichthys mirabilis from three locations: Hayward, CA, San Diego, CA, and San Felipe, Mexico, were analyzed using isozyme electrophoresis and Amplified Fragment Length Polymorphism (AFLP), a recently developed DNA fingerprinting technique. Three questions were posed: 1) Are the populations of Gillichthys mirabilis separate or interbreeding? 2) If the populations are interbreeding, to what extent does interbreeding occur?, and 3) Is AFLP a sensitive and reliable technique to use for a population genetics study of this species?
In the isozyme work, staining for malate dehydrogenase revealed an allele that was present only in the San Diego fish, suggesting little gene flow among the three populations. Preliminary AFLP results show some differences between the Hayward and San Diego samples, as well as the potential for AFLP to be a powerful technique. More in-depth studies, however, will be needed to draw definitive conclusions about the population structure of Gillichthys mirabilis.