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Amber May Release Ancient Disease-Causing Microbes



DOCTOR WARNS OF DANGER OF RECOVERIES FROM ANCIENT AMBER

THE MEDICAL JOURNAL
By MIKE WOODS

The Toledo Blade

Genetic research on prehistoric organisms entombed in amber could release
ancient disease-causing microbes into the modern world, an expert has warned.

Amber is the fossilized resin that bled from trees millions of years ago,
sometimes entombing and preserving insects, pollen, plant fragments and
microorganisms.

In research reminiscent of that depicted in Michael Crichton's thriller,
"Jurassic Park," scientists are trying to recover ancient DNA from amber
-preserved insects, leaves, pollen and other material.

A major target is dinosaur DNA from blood-sucking insects. Less well-known are
intensive efforts to recover ancient bacteria, viruses and fungi from amber,
Dr. David Grimaldi told the 208th national meeting of the American Chemical
Society. He is chairman of the department of entomology at the American Museum
of Natural History in New York City.

Grimaldi said that the research carries a risk of infecting modern organisms
with ancient pathogenic - disease-causing - microbes. The microbes could be a
threat not just for humans, but for domestic animals and plants.

He cited an example - the possibility that bacteria in certain amber-preserved
beetles could cause disease in modern trees. The bacteria, he said, almost
certainty killed prehistoric trees.

"Isolating viable spores of fungus from amber would - or should - be a very
controversial project," Grimaldi said. "Extraction and culture of bacteria and
viruses from amber, however, is a hit-and-miss approach. No precautions are
made to screen out potentially pathogenic species."

Indeed, he noted that science has little ability to even determine which ancient
species of microbes would be pathogenic. Bacteria, he explained, are perhaps the
least-understood of all modern organisms. A speck of forest soil contains
thousands of species, most of which have not been studied.

Grimaldi said that amber is a good material for preserving ancient organisms,
since it seals them off from destructive effects of air. Flies preserved in 
amber for 40 million years, for instance, appear as lifelike as modern
houseflies.

Microbes may preserve especially well in amber, since their DNA is simple.
Some experts believe that scientists eventually will recover viable bacteria -
bacteria capable of growing and reproducing - from amber.

Some bacteria, for instance, go into a dormant stage by forming thick-walled
"cysts." The cysts can survive heat, dryness, exposure to radiation and other
unfavorable conditions. Once placed in a moist, suitable environment, the
bacteria emerge from dormancy and resume life.

Similar risks come from efforts to isolate fragments of the genetic material DNA
from prehistoric microbes, Grimaldi said. He cited efforts in at least one
laboratory to graft genes from an extinct bacterium into the DNA of its close
living relative.

"In the worst scenario a unique pathogenic feature would unwittingly be infused
into a living species of bacteria," Grimaldi said. "Ethical concerns over
resurrecting possible pathogenic, extinct microorganisms are certainly
justified."

Grimaldi said that such concerns halted the research of one Japanese geneticist
who isolated from a prehistoric fruit fly genes that control body development.
The scientist wanted to graft the genes into a living fruit fly, but his
university halted the project.

There have been at least three reports of the possible isolation of prehistoric
bacteria from amber. The scientists used scrupulously sterile conditions to
rid the amber of modern bacteria contaminating the fine cracks in its surface.

But Grimaldi said the reports are open to question, because there is no way
proving that the bacteria were not modern contaminants from undiscovered species
living today.