Associated Press/ExhibitEase LLC, Steven W. Marcus
This artist's rendering, provided by the Mammoth Genome Project, Penn State University, portrays the unraveling of the genetic code of an extinct animal, the Ice Age's woolly mammoth -- here encased in ice.
By David Templeton Pittsburgh Post-Gazette
Two Penn State University professors have mapped much of the genetic code of the woolly mammoth, a possible first step toward re-creating the extinct beast in the next 10 to 20 years.
"It could be done. The question is, just because we might be able to do it one day, should we do it?" asked Stephan Schuster, professor of biochemistry and molecular biology and co-author of the new research.
The genome-sequencing project, first of its kind on an extinct animal, also revealed that two groups of woolly mammoths existed, one that went extinct 45,000 years ago and another that went extinct in 10,000 B.C.
In the movie "10,000 B.C.," the mammoth is described as the mightiest of beasts, and professors Schuster and Webb Miller said the same description applies to the creature's genetic material.
It could include as many as 4.7 billion base pairs -- or about 1.7 billion more than the human genome.
"We pushed the technology a very long ways forward in this paper and sequenced 250 times more DNA from an ancient animal than was ever done before," said Dr. Miller, professor of biology, computer science and engineering. "Being able to sequence old DNA lets you look at evolution directly.
"Before, you were forced to make inferences based only on data from living species," he said.
"This is an amazing achievement," said Alex Greenwood, an Old Dominion University biology professor who studies ancient DNA and was not involved in the mammoth research.
The findings to date, with more than half of the genome now sequenced, are helping scientists better understand the ancient cousin of African and Asian elephants.
The research, published yesterday in Nature, helps confirm that the woolly mammoth was not a homogenous group, but rather two distinct groups.
It also absolves humankind from forcing at least the first group into extinction. It will give researchers a tool to investigate whether a lack of genetic diversity contributed to the extinction process. Factors could have included disease and climate changes.
Drs. Miller and Schuster said their work also proves that the woolly mammoth and the African elephant are 99.4 percent identical, with the woolly mammoth containing gene changes that allowed it to survive the cold temperatures of Siberia and northernmost North America.
Similar in size to the elephant, the mammoth had a shorter rear end and a hump on its back, along with long hair and curling tusks. The mammoth separated from other elephant lines about 6 million years ago, about the time the human species separated from ancestors of today's primates.
To obtain the DNA, the scientists relied on 20 balls of mammoth hair found frozen in Siberian permafrost. Past efforts to analyze ancient DNA often used material extracted from fossilized bones, which frequently became contaminated with bacteria, viruses and parasites over thousands of years, leaving only about 1 percent of actual bone. Hair has fewer contaminants because its keratin casing better protects the DNA.