Minimal nucleotide sequence divergence detected in the sea urchin Strongylocentrotus, droebachiensis by direct sequencing of enzymatically amplified DNA

• Main Author: Stice, Ligaya
• Other Authors: Chemistry
• Format: Text
• Language: unknown
• Published: University of Hawaii at Manoa 2014
• Subjects: Arctic; Arctic Ocean; Pacific; North Atlantic
• Online Access: http://hdl.handle.net/10125/32196

The assumptions that have been made concerning mitochondrial DNA (mtDNA) variability have been based on studies on Drosophila and vertebrates. Recent studies on marine species show marked differences in comparison to terrestrial populations. Terrestrial populations tend to show considerable amounts of mtDNA variability accompanied by distinct population structure. My study is concerned with the variation present in the mitochondrial genome of Strongylocentrotus droebachiensis populations. This sea urchin has a distribution throughout the Arctic Ocean and in both the North Pacific and the North Atlantic Oceans. Based on the previous assumptions about mtDNA variation, we should expect large degrees of sequence difference due to the mere magnitude of geographic distances involved. Using the polymerase chain reaction we have been able to determine the sequence of the ATPase 6 gene in the mitochondrial genome of six S. droebachiensis sea urchins from the North Atlantic. These sequences were compared both among themselves and to a S. droebachiensis urchin from Puget Sound, Washington. Of the approximately 1500 base pairs that were sequenced, only one base substitution was found. This indicates dramatic differences between the amounts of variation present in the sea urchin genome versus the greater diversity found in genomes previously studied.