Extracting DNA from Homo floresiensis has been tried in the past with no luck. Nature News reports on a new attempt to obtain DNA from a Homo floresiensis molar. What struck me is interesting from the story is this bit:
Adler’s team – which included some researchers involved in the original H. floresiensis DNA recovery attempt – compared the impacts of various sampling techniques on DNA from the mitochondria of 40 human specimens from around the world, which had been dated up to 7,500 years old. The results have been accepted for publication in the Journal of Archaeological Science2.
Most genetics research on ancient teeth has focused on the inner tooth tissue, dentine, but Adler’s team found that cementum, the coating of the root, was a richer source of DNA.
Drilling is a technique commonly used to sample teeth and bone, because it minimizes damage to the precious specimen. But Adler’s team found that the heat generated at standard drill speeds of more than 1,000 revolutions per minute (RPM) destroys DNA rapidly, causing yields to be up to 30 times lower than for samples pulverized in a mill. Reducing the drill speed to 100 RPM alleviated the problem.
The Max Planck team sampled dentine from the hobbit tooth in its early attempt to recover DNA, but it is unclear what drill speed was used. And although the ACAD scientists used the lower drill speed, they also concentrated on dentine. They will target cementum in their next attempt.
The footnote in the above quote goes to the article below:
Survival and recovery of DNA from ancient teeth and bones Adler et al Journal of Archaeological Science
(If some one could send my a copy I would appreciate it). Thanks, I have the article now!