Woolly Mammoth Hair Provides DNA

Drawing of a woolly mammoth. (Credit: Penn State University)

ScienceDaily (Sep. 27, 2007) — Stephan C. Schuster and Webb Miller of Penn State, working with Thomas Gilbert from Copenhagen and a large international consortium, discovered that hair shafts provide an ideal source of ancient DNA -- a better source than bones and muscle for studying the genome sequences of extinct animals. Their research achievement, described in a paper to be published in the journal Science on Sept. 28, includes the sequencing of entire mitochondrial genomes from 10 individual woolly mammoths.

The research team obtained hair from 10 woolly mammoths collected from a wide swathe of northern Siberia and with dates of death spanning approximately 38,000 years -- from 50,000 years to 12,000 years ago.

"DNA in bones and muscle usually degrades and becomes contaminated with genetic material from other sources such as bacteria, limiting its usefulness in scientific studies," Schuster explained. Because only a tiny proportion of ancient bones and muscle are preserved in such a way that uncontaminated DNA can be recovered, research with such materials has involved laborious efforts, sometimes spanning as long as six years for a single study. In contrast, Miller said, "Once I get the data from the genome sequencer, it takes only five minutes to assemble the entire mitochondrial genome."

Source of quotes:
http://www.sciencedaily.com/releases/2007/09/070927141921.htm