Amara Earley Bray and Dr. Dennis K. Shiozawa, Zoology

Recent studies of native trout in Utah have found that populations in separate stream drainages tend to have unique mitochondrial DNA lineages. The association of lineage with drainage implies that the trout tend to remain within their own streams and do not readily migrate to adjacent streams.

I initiated a similar study on populations of Cottus bairdi in the Provo, Weber, and Spanish Fork rivers. I collected in two sites on the Provo River: one across from Squaw Peak Trail Road, and one on the Upper Provo north of Deer Creek Resevoir. The site on the Weber River was at Peoa northwest of town one n-file from the bridge of State Highway 32. On the Spanish Fork River I sampled in two sites, one on Hobble Creek at the US Forest Service boundary, and the other on Thistle Creek four miles upstream from Thistle Junction. Cottids have had a reputation as being difficult to extract DNA from. This was my first obstacle. I attempted to extract first from fortnalin preserved museum specimens. In two different trials using differently prepared formalin preserved specimens I got negligible results. Frozen museum specimens didn’t bring any more success despite trying a broad range of techniques and sample populations. Fresh specimens however brought about a 66% success rate in extraction. Success seemed dependent on the time the specimens were left at room temperature after being sacrificed. With even a twenty to thirty minute waiting period on ice the DNA seemed to degrade. I think that may have been the problem with the preserved specimens. When I extracted tissue, I immediately placed the remaining specimens in a negative eighty degree freezer and these fish yielded high percentages of successful re-extractions of DNA two months later.

Apart from the problems in degradation of DNA in the fish themselves, once the DNA was extracted I only had a window of two to three weeks for analysis before the template started to degrade. I amplified four regions of mitochondrial DNA: CytB, ND 1, ND2, ND 5/6, and cut the regions with nine different restriction enzymes: Alu 1, HaeIII, Hinfl, Mbo 1, Rsa 1, Cfo 1, Mse 1, Msp l, Ddel. Even with my best extractions only about half amplified the larger regions (NDI, and ND5/6) of the mt DNA. After a few weeks no amplification was possible.

Nevertheless I found one and possibly two polymorphisms. The clear polymorphism occurred between the Weber River and the Upper Provo River sites. In the Cyt B region cut with the restriction enzyme HAEIII I saw two definite band patterns which I named type J and type N. In the Weber River I found 87.5% type J and 12.5% type N. In the Upper Provo site I found exactly the opposite: 87.5% type N and 12.5% type J. In all the other sites I found all type N patterns. I hypothesize that perhaps there was one ancestral type for the Utah Lake drainage (type N) and another type (type J) for the fish of the Weber River drainage. All of the river sites I sampled were in the Utah Lake drainage except for the Weber river. This would explain the type N patterns for all of those fish. But since both the Weber and the Provo Rivers enter the Kanas/Oakley alluvial plain, there has been historical transfer of waters of the two rivers and prehistoric of type N fish from the Provo system to the Weber and the movement of pattern J from the Weber to the Provo system.

The second polymorphism isn’t as clear. In the Cyt B region when cut with the restriction enzyme Msp I saw a difference in banding patterns between the Thistle Creek and Hobble Creek sites. The fish were monomorphic in each of the sites but different from each other. I designated these types B for the Thistle creek pattern and M for the Hobble creek pattern. Unfortunately the restriction digests did not work for the other stream sites so it is not possible to interpret the data geographically. But it raises some interesting questions in terms of common ancestry.