ANCIENT, HISTORIC, MODERN SALMON DNA ANALYSIS
Researchers from Washington State University work to document the chronology of change in salmon DNA in relation to human impacts.
Brian Kemp, Washington State University (WSU) Department of Anthropology
Bobbi Johnson, WSU School of Biological Sciences
Gary Thorgaard, WSU School of Biological Sciences
Salmon genotypes are routinely compared across watersheds—but not across time—even though human activities such as industrial fishing, dam building, and transplantation and mixing have profoundly affected salmon populations over the last two centuries. This project intends to correct that knowledge deficiency by mapping the genetic structures of upper Columbia basin Chinook salmon from the 19th century and the dam-building years (1930-1950). It will compare these structures with current ones and ancient genotypes derived from DNA preserved in 7,600-year-old archeological vertebrae samples. By producing a high-resolution picture of genetic change in response to major human impacts, this effort intends to add a fifth “h” (history) to “harvest, hydropower, hatcheries and habitat,” the familiar tetrad of influences that currently guide salmon management. The informed baselines thus developed may lead to more effective evaluation, restoration, and reintroduction of salmon populations.
Washington Sea Grant-supported researchers sought to develop and evaluate improved methods for amplifying DNA from degraded samples. They developed a modified PCR protocol dubbed “Rescue PCR” and systematically tested it.
The team developed a cost- and time-efficient protocol that improves the success rate for recovering DNA from archeological samples, which are often difficult to process. This protocol can be implemented in the lab without specialized equipment or supplies and is useful for population-based studies of ancient samples.