Ancient Penguin DNA to Improve Accuracy of Genetic Dating Techniques
16.11.2009 - Flora & Fauna, Other, Antarctic
A new study using penguin bones from Antarctica 250 to 44,000 years old might change the face of genetic aging measurement techniques. The study, which involved researchers from Oregon State University (OSU) and was published in the journal Trends in Genetics, indicates existing genetic age measurement techniques might have been underestimating the age of many specimens by as much as 200 to 600 percent.
Until now researchers have been using the rates of genetic mutations in cells to determine the age of ancient biological samples, and in a technique called phylogenetic comparison, used that information along with fossil evidence to date fossils and map the history of the evolution or species. Yet according to Dr Dee Denver, an evolutionary biologist with the Center for Genome Research and Biocomputing at OSU, in order for the genetic analysis to be accurate, it is necessary to have the correct molecular clock rate, and conventional DNA analysis has not been capturing many genetic changes. The doubts this study raises about many traditional dating techniques has the potential to force a widespread re-examination of how different species may have split from each other.
Although some earlier work based on small amounts of DNA indicated the same problem, this report holds greater weight, as it is based upon a wide range of mitochondrial DNA from bones between 250 and 44,000 years old well preserved by the sub-freezing temperatures in Antarctica.
