Pristine DNA discovered in fossilized eggshells

[Ian David]

Finding could advance sequencing studies of ancient animals.

Extremely well-preserved DNA discovered in the fossilized eggshells of extinct bird species suggests that they could be a source of ancient genetic material for sequencing efforts. Eggshells are commonly found at fossil sites worldwide. But, to date, no one has described recovering DNA from them successfully.

Now, evolutionary biologist Michael Bunce and his graduate student Charlotte Oskam at Murdoch University in Perth, Western Australia, together with an international team of scientists, have recovered DNA from fossil eggshells by dramatically improving on the process used to extract it.

Conventionally, scientists remove calcium salts from fossil eggshells using decalcifying solutions before extracting DNA. Unless they are removed, the salts prevent DNA from sticking to the silica column used during the purification process. But eggshells are predominantly (97%) made up of calcium carbonate crystals that are embedded in a protein matrix that forms the shell. This led Bunce and Oskam to wonder if the decalcification process itself might be washing away DNA preserved within the shell.

To find out, the team separately measured the amount of DNA in both decalcified eggshell powder and the waste solution used to decalcify them. They found DNA in the decalcification solution but not in the powder — suggesting that researchers have been throwing away precious ancient DNA.

"This is a quite exciting piece of work. It is rather embarrassing for the ancient-DNA community that we have not tried this before," says biologist Michi Hofreiter of the University of York, UK.

More:
http://www.nature.com/news/2010/100310/full/news.2010.111.html

[Deep13]

1. That can only mean one thing.

Seriously, that's very interesting. Another nail in the already nail-studded coffin of creationism.