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La Jolla (USA) ) Dated between 9,000 and 9,600 years old, the exceptionally preserved bones could potentially produce the oldest complete human genome from the continent.

 

Scientists Fight University of California to Study Rare Ancient Skeletons

Rex Dalton

Source - http://www.wired.com/wiredscience/2011/05/ucsd-skeleton-fight/ 

 

SAN DIEGO — Two ancient skeletons uncovered in 1976 on a bluff overlooking the Pacific Ocean, during construction at the home of a University of California chancellor, may be among the most valuable for genetic analysis in the continental United States. Dated between 9,000 and 9,600 years old, the exceptionally preserved bones could potentially produce the oldest complete human genome from the continent.

But only if scientists aren’t barred from studying them.

Attempts to unlock the skeletons’ genetic secrets are stalled in a dispute pitting UC scientists against their own administration. Five of the scientists wrote with alarm in a letter published May 20 in the journal Science that UC administrators aren’t allowing studies on the skeletons, which were discovered on property owned by UC San Diego in La Jolla, California.

The La Jolla skeletons. (Jan Austin/Santa Monica Community College).

Before samples can be extracted for genetic analysis, the scientists fear administrators will give the bones to politically powerful local Native Americans who could permanently block study.

“To give them away without study, would be like throwing the genetic crown jewels of the peopling of the Americas in the ocean,” said Eske Willerslev of the University of Copenhagen in Denmark, who is among about a half dozen researchers who have unsuccessfully sought in recent months to sample or study the bones. “It would be a major loss for all, including Native Americans.”

A few studies were done years ago on the skeletons before UC withdrew access to them, but recent technological advances would allow scientists to do much more, including a digital skull calibration and possibly a full genome sequence.

“The potential loss of the La Jolla skeletons would have a profoundly negative impact on our knowledge of the peopling of the Americas,” wrote the authors of the letter, led by Margaret Schoeninger, an anthropologist at UCSD.

Science letter co-author Tim White, a prominent paleoanthropologist at UC Berkeley, told Wired.com, “Administrators are doing everything they can to ignore the scientific value of the specimens. They are trying to illegally repatriate them to a lobbyist for a dozen San Diego County tribes.”

UC officials are seeking to provide the skeletons to the Kumeyaay Nation east of San Diego under a complex process guided by the federal Native American Graves Protection and Repatriation Act (NAGPRA). But critical scientists say NAGPRA requirements aren’t being followed properly, setting the stage for a potential legal battle over the bones.

“This is Kennewick Man II,” White said, referring to the long federal court battle in 2004 when scientists won the right to study bones found in Washington.

In a May 11 letter, Mark Yudof, president of the 10-campus UC system, authorized UCSD chancellor Marye Anne Fox to dispose of the bones — after clarifications are made to a report done under NAGPRA requirements, and other tribes that may be interested in the bones are consulted.

Steve Benegas, the repatriation spokesman for the Kumeyaay nation’s 12 tribes, said they are entitled to the bones and to decide about future analysis. Some Native Americans believe scientific research amounts to desecration of remains, and Benegas said he personally is against studies.

“The university has handled this poorly over the years,” he said. “We have no trust in them. They have treated the remains of our ancestors without respect.”

Excavation of the La Jolla skeletons. (photo by Kirby Smith, courtesy of Jeff Bada).

One of the previous analyses done years ago showed the bones have connective tissue and amino acids that are used in cell function. This means it is very likely ancient DNA can be extracted. And two skeletons buried together offers a rare opportunity to compare their genomes to see if they were related.

Genetic reports on human remains this old on the continent are very limited. In 2007, researchers published about 7 percent of the maternally inherited mitochondrial genome of bones found in a cave in southeast Alaska that are about the same age as the La Jolla skeletons. But the full genome of that individual hasn’t been sequenced and published, and DNA from bones found in wet caves can be more difficult to extract and analyze.

“The La Jolla skeletons are very special,” said Brian Kemp of Washington State University. Kemp was part of a team that retrieved samples from the Alaska bones before they were repatriated in 2007 to local tribes in an exchange seen as model of cooperation among scientists and Native Americans.

Anthropologist Robert Bettinger of UC Davis, another co-author of the Science letter, says he and others would like a similar arrangement for the La Jolla skeletons.

Scientists say UC is overlooking two key points. First, there has been no official determination the bones are actually from ancestors of modern Native Americans. Though many tribes believe their history goes further back, scientists can only confidently trace the ancestry of Native Americans to about 7,000 years ago.

One of the La Jolla skulls shortly after excavation. (photo by Kirby Smith, courtesy of Jeff Bada).

Second, scientific evidence shows skeletons around this age are not always related to those who now live near burial sites. For example, last year Willerslev sequenced the genome of a 5,000-year-old man in Greenland and found he was descended from Siberian ancestors, not today’s Greenland tribes.

“It is unscientific to provide them to local people,” said Willerslev.

Since the NAGPRA rules were first issued in 1990, thousands of bones have been repatriated, almost all of which were shown to be culturally affiliated to the tribes that received them. But last year, federal officials issued new NAGPRA rules that make it easier to return bones and funerary objects that are not culturally affiliated to tribes.

Scientists and museums have been considering a legal challenge to the new rule, fearing the loss of many valuable specimens. The La Jolla skeletons could end up as the case by which that rule is challenged.

UCSD scientists determined the La Jolla skeletons are not culturally affiliated to any tribe. In fact, isotopic analysis done 30 years ago in Schoeninger’s lab (and published in 2009) showed the bones reflected a diet of seafood and marine mammals, not terrestrial foods such as nuts and wild fruits like the early Kumeyaay ate.

Schoeninger suspects UC’s efforts to give the bones to the tribe stem from a plan to renovate the chancellor’s house, and she says that Benegas, the tribe spokesman, told her as much.

UCSD officials want to rebuild the home, also known as University House, because it has become uninhabitable due to structural problems. They have received pledges totaling at least $6 million for the project from wealthy donors. Earth moving for the renovation is expected to uncover more ancient bones, which could cause costly delays if the tribes make a political or legal issue out of it.

By providing the two skeletons to the Kumeyaay, Schoeninger believes UCSD officials are hoping that refurbishing the home will go smoothly.

When asked about this theory, Benegas chuckled as he told Wired, “We wouldn’t be talking if they weren’t trying to rebuild the chancellor’s house.”