Iceman's DNA

Scientists in Italy and Germany announced Tuesday that they had finally sequenced the DNA of Oetzi the Iceman. This mummy was found frozen in the Alps nearly 20 years ago and is a remarkable 5,000-year-old human specimen.

Researchers have said they may be able to answer some basic biological questions about humans at that time, and what connection they may have to humans of today.

"It tells us a lot about the iceman itself, about his immune system, about how his genetic data is composed," said Albert Zink of the European Academy of Bozen in northern Italy and head of the Institute for Mummies and the Iceman.

"It tells us maybe the diseases that he suffered from, fertility diseases, and it tells us clues about modern times," he told Deutsche Welle. "We can, for example, say are there still some living relatives of the Iceman? Or are there any changes in the genome of the person who lived 5,200 years ago to today's population?"

DNA sequencing was first attempted 15 years ago

By sequencing DNA, scientists now have a blueprint of Oetzi' genetic structure. They know the order of the base pairs of his DNA, but still have to decipher exactly what genetic traits they correspond to; these range from eye color to diseases he may have suffered.

Zink added that he and his team have their work cut out for them.

"We definitely want to show how the iceman was composed: did he carry some genes that go into directions of some diseases?" he said. "We want to know if he could digest milk, for example. These are things that are important for the evolution of populations."

Scientists first tried to sequence Oetzi's DNA in the mid-1990s, but the computer and processing technology available at that time was far too primitive to adequately analyze damaged DNA samples.

Anne Stone, now a professor of anthropology at Arizona State University in the United States, was among the team that worked on the Iceman at that time when she was a graduate student. While she's glad that the task has finally been completed, she cautioned about jumping to too many conclusions about humans from the Copper Age.

"It is a sample of one," she said in an interview with Deutsche Welle. "For us to really say something about that time period you need a sample of 25 to 50 individuals."

Iceman's DNA may provide links to modern humans

But beyond simple facts about the Iceman's physiology, Zink also said Oetzi may provide answers to questions about how human diseases like diabetes have evolved, which may lead to better treatments in the future. Also, scientists wonder if elements of his DNA may still persist in the Alpine region.

"It would be quite interesting to compare this data from the Iceman to people from this region and we can say whether there is a close link or maybe he is somehow distant from these people," Zink said. "Because it could also be that his lineage is somehow extinct or if his genes are still around in our population."

While the scientists will have plenty of material to evaluate and analyze, results will likely arrive faster than when they first tried mapping Oetzi's genetic makeup, said Andreas Keller, a bioinformatics expert at Febit, a German company in Heidelberg who helped sequence the Iceman's DNA.

"We have 3 billion base pairs that we have to look at and we are in the middle of that process," he said. "What we can learn over the history of the past 5,000 years will show the final results and I expect that we will have this in about four months, or so."

Scientists announced the sequence of the human genome over a decade ago, and continually announce DNA sequences of other organisms, including ancient humans.

Author: Cyrus Farivar
Editor: Sean Sinico