Three years ago, Japanese scientists said they hoped to find frozen mammoth sperm and impregnate an elephant and raise the offspring in a safari park in Siberia. But using genetics to engineer a mammoth makes more sense, Schuster said.

Anthropology professor Hendrik Poinar of McMaster University in Hamilton, Ontario, said he no longer considers such ideas impossible. Poinar, who wasn't part of Schuster's study but consulted on the movie "Jurassic Park," said director Steven Spielberg may have had it right when he told skeptical scientists: "This is the science of eventuality."

There are two possible ways to use this new genetic map to make a mammoth, and both involve creating a mammoth embryo and implanting it into its elephant cousin. Both methods are incredibly complex and rely on intricate genetic manipulation because the mammoth DNA is not suitable for cloning.

One approach requires scientists to start with an elephant cell and genetically engineer it to match the DNA code of a mammoth.

The other method involves synthetic biology in which scientists would create life forms from scratch. Once this technique is developed — and leaders in the field say it is just three to 10 years away — scientists would follow the mammoth recipe to build a mammoth cell.

An easier option would be to examine what makes the mammoth different from its closest cousin, the African elephant, and create a hairy hybrid to sit in zoos. "People would like to see a hairy elephant," said George Church, director of computational genomics at Harvard Medical School.

The more practical side of the research is to better illustrate the evolutionary differences between mammoths and elephants and even humans and chimps, said Church, who was not part of the study.

Elephants and mammoths diverged along evolutionary paths about 6 million years ago, about the same time humans and chimps did, Schuster said. But there are twice as many differences between the genetic makeup of chimps and humans as those between elephants and mammoths.

"Primates evolved twice as fast as elephants," Schuster said. But some animals such as rodents have had even more evolutionary changes, indicating that their development might have to do with size or metabolism, said study co-author Webb Miller.

Another interesting finding: In the 50 or so species with mostly mapped genomes, there are certain areas where the genetic code is exactly the same in all the animals — except the mammoth.

In other animals, these proteins "stayed the same for a very long time," said Miller, professor of biology and computer science at Penn State. "I don't know what it means. All I did was find them."

Miller and Schuster noticed that most of the mammoths they examined had far less genetic diversity than other species still alive, and that may also give a clue to the biology of extinction.

So the two are also applying what they learned from the Siberian behemoth to their other efforts to help save Australia's endangered Tasmanian devil, which has the same lack of genetic diversity.