Applied Biosystems Inc.'s automated DNA sequencers will beused in a project starting next week in England to identify thegenetic pattern in bones thought to be those of Czar Nicholas IIand his family.

Applied Biosystems is sponsoring the project, which willemploy the company's fully automated DNA sequencer, a one-lane sequencing process that uses refined, four-dyefluorescent labeling methods and produces what the companyclaims are very accurate results.

The alleged czar's remains will be examined by mitochondrialDNA sequencing that identifies the genetic pattern thatcharacterizes members of the same family. This DNA patternis inherited through the maternal line and is sufficientlydistinct to confirm family relationships through manygenerations. The testing process will involve taking hairsamples from living relatives of the Russian Romanov familyto check against the DNA of the bones.

According to Jackie Cossman, director of corporatecommunications at Applied Biosystems of Foster City, Calif.,one-lane sequencing makes interpretation of the results easierthan the four-lane format used in manual methods such as agel apparatus.

"Using manual techniques, you would typically have to run fourlanes because you don't have a mechanism to distinguishcolor," Cossman said. "And because of gel inconsistencies, eachlane of DNA runs at a different rate."

ABI's automated DNA sequencer is computerized, so data can bematched easier than with lengthy manual processes. Even so,Cossman said about 90 percent of DNA sequencing is still donemanually.

The British Broadcasting Corp. instigated the czar project.According to the BBC's Nigel McCleary, a recent development inforensic research that enables DNA extraction from very oldbones has been successfully used on 350-year-old bonesrecovered from the British Civil War and will complementABI's DNA sequencing technology on the project.

Cossman said sales for ABI's DNA analysis products aregrowing rapidly, jumping 60 percent this year from 1991. Mostof these sales are to government, biotech, pharmaceutical anduniversity research institutions.

But Cossman reported that about 20 percent of sales are tonon-traditional laboratories. These include test sites at labsoperated by the Royal Canadian Mounted Police (RCMP), the FBIand the Armed Forces Institute of Pathology (AFIP), which ABIhopes will adopt the products for use, Cossman said.

Mitch Holland, a research scientist for the Armed Forces DNAIdentification Laboratory, part of the AFIP in Washington, D.C.,said his lab is using ABI's DNA sequencer for humanidentification purposes.

It is looking specifically at mitochondrial DNA because of thefrequency with which it occurs compared with regular DNA.

"We are generating data bases so we can place weight onidentifying individuals using sequence analysis," he said.Holland said the technique has been used successfully toidentify Vietnam War remains. The only methods previouslyavailable were such manual methods as conventionalanthropology or odontology.

Ron Fourney, section head for biology research anddevelopment with the RCMP, said the courts are still using asingle-locus approach to DNA typing (or fingerprinting) basedon a probe that recognizes a different polymorphic region onthe chromosome. Each probe constitutes one test, and generallyfour or five tests are run that represent the same number oflocis -- the place of residence of a gene.

However, Fourney said polymerase chain reaction (PCR)technology allows researchers to work with much smallerquantities of material, such as a blood sample, or with badlydegraded samples.

According to Fourney, further advances using fluorescentmethods, such as ABI's sequencer, gives a faster, moresensitive, automated approach to the DNA typing procedurewith quality assurance built in "It's the most significantadvancement to hit forensic science," he said.

-- Michelle Slade Associate Editor

(c) 1997 American Health Consultants. All rights reserved.

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