As an “amateur” ecologist, migratory patterns of salmon has always intrigued me. In the May 2006 issue of American Laboratory, Mark Springer’s interesting review on salmon genotyping caught my eye for several reasons.
According to the Human Genome Project Information and The National Center for Biotechnolgy Information single nucleotide polymorphism or (SNP) are DNA sequence variations that occur when a single nucleotide (A,T,C,or G) in the genome sequence is altered. For example a SNP might change the DNA sequence AAGGCTAA to ATGGCTAA. “For a variation to be considered a SNP, it must occur in at least 1% of the population. SNPs, which make up about 90% of all human genetic variation, occur every 100 to 300 bases along the 3-billion-base human genome.”
The use of molecular markers to identify salmon has been a evolving technology for thirty years according to Springer. What has been an interesting development in the use of this biotechnology, is how it compares to the functionality of microsatellites, which were initially introduced to the Fish and Game industry.
Microsatellites, another form of genetic marker is based on different-sized fragments of DNA collected from non-coding regions of an oranism’s genome(Smith, CT 2005). One of the challenges mentioned by Springer, is the difficulty of transferring microsatellite data between laboratories, which is essential when compiling statistics in regards to the migratory patterns of the salmon. Moreover, inferences can be made about population structures and differences with the utilization of microsatellites or SNP technology.
As an “amateur” ecologist, I was particularly interested in the environmental threats to the salmon population, particularly the sockeye chum. Who are confronted with the “possible” consequences of global climate change…which appears to reveal itself in thick algae blooms off the Western Coast of Alaska. These one-celled marine plants live in large numbers throughout the ocean (NASA, 2005). Consequently, as the salmon migrate beneath these blooms, they often face starvation, due to the poor micro-nutrients provided by these phytoplankton.
As SNP genotyping gains more footing in the Fish and Game Industry, I am hopeful that this advanced form of gentotyping may provide more useful data of the migratory patterns of this important species, which may afford scientists to better forecast trends and improve the management of salmon stocks.