Mitochondrial D-Ioop PCR-RFLP\u27s Detect High Variability in a Paddlefish (\u3ci\u3ePolyodon spathula\u3c/i\u3e) Population

The paddlefish (Polyodon spathula) is an evolutionarily ancient, long-lived, highly migratory, cartilaginous fish native to the Missouri, Mississippi and several Gulf Coast drainages (Gengerke, 1986; Russell, 1986). Paddlefish populations have declined along with a concomitant reduction in their range partly due to impoundments, channel alterations and overharvesting. To address some of the problems that arise when restoration of a species such as paddlefish is undertaken, genetic analysis becomes necessary. To ensure that stocking programs are maximized, inbred and conversely, genetically unique fish populations must be identified. Previous genetic analysis was either biochemically performed or at the DNA-level. Livers were removed to isolate mitochondrial DNA which meant the sacrifice of the individual(s). With the rapid advances in molecular biological techniques, non-invasive genetic analysis can now be obtained. This study demonstrates a method to analyze at the DNA level without the need to sacrifice the individual. By selectively targeting the genetic site of interest and using a technique known as PCR (polymerase chain reaction), millions of copies of a DNA fragment can be produced and then tested for variations between 2 or more individuals by restriction fragment length polymorphism (RFLP)