WASHINGTON (Reuters) - Experts from across the United States will start taking tiny samples on Wednesday from the Kennewick Man skeleton found in southern Washington state in 1996 to see if they can do DNA tests.

Such tests would help show the origin of the 9,300-year-old skeleton and might help settle claims about whether the remains can be linked to Native American groups.

"Before we go through the further destruction of taking enough of a sample for the DNA, we are going to take very tiny samples ... and look at those chemically,'' Frank McManamon, chief archeologist for the National Park Service, said in a telephone interview.

He said the bones must contain enough collagen to test for DNA. Collagen may have survived millennia in a grave but could have broken down when the skeleton washed into the Columbia River, where it was found.

"It could have gone through cycles of being wet and dry. That's the sort of variation that can really destroy bone and break it down,'' McManamon said.

Five Native American tribes claim Kennewick Man, found in 1996 near the town of Kennewick in eastern Washington, as an ancestor. The tribes have vigorously opposed any scientific testing of the remains and want them reburied.

The Interior Department has ruled that Kennewick Man was Native American under the guidelines of the Native American Graves Protection and Repatriation Act. The act says remains found to predate the 1492 Columbus voyage to America must be turned over to local tribes.

But the Department wants to do tests to try and determine more about the genetic origin of the remains.

McManamon said if there is enough preserved material to yield DNA, experts would be looking for both mitochondrial DNA, which is passed down virtually unchanged from mother to child, and DNA from the Y chromosome, which is passed from father to son.

Both can act as a kind of genetic clock, and are commonly used to trace the origins of people.

It is not uncommon to get DNA out of old remains. In 1997 British scientists used DNA to link a 9,000-year-old skeleton known as ``Cheddar man'' to a living Englishman, presumably a distant descendant.

And researchers have found bits of DNA in Neanderthal remains more than 20,000 years old.

"We also have a team of expert physical anthropologists who are doing another examination of the remains to determine what kinds of treatment it received,'' McManamon said.

Experts from the University of New Mexico, University of California, University of North Carolina and elsewhere are on the team.

Because the bones were not found in a grave, archeologists do not have the usual clues to work with. They want to look at the surface the bones to get hints about what sort of treatment, if any, the body received after death.

As for the DNA, it might be able to show if Kennewick Man belongs to one of four identified haplogroups, or genetic groups, that have been identified among American Indians.

Genetic studies so far suggest that the Americas were settled in four separate migrations. Linguistic studies tend to support this.

Kennewick Man sparked debate over the origin of American peoples after cranial studies showed that he looked different than modern Native Americans.

But government officials note that he bears little resemblance to any modern people and say physical characteristics among many ethnic groups have changed over such a long period of time.

Theories about the possible origin abound, from those who say Kennewick Man looks European to those who find a resemblance to the present Ainu people of Japan.