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Last Updated

15 Dec 2002

Source: Wall Street Journal, February 7, 2002.


FBI's New Approach in Its Search For Anthrax Mailer Focuses on Labs


The Federal Bureau of Investigation is taking a new tack in its hunt for the anthrax mailer.

It's betting that genetic and other scientific analyses will narrow down the number of laboratories that hold anthrax strains closely related to the one used in the terror attacks. As soon as that happens, the agency plans to bear down on those labs with the full force of its investigative powers.

"We can get very focused and very aggressive," says a senior law-enforcement official involved in the investigation.

This official, who spoke on the condition of anonymity, said that the FBI will likely deploy lie detectors and subpoena employee records to compare the handwriting on them with the letters and envelopes that contained the anthrax. "When we get the science done," said this official, "we're going to bring back the police work and move forward."

But the FBI's plan could be thwarted by lax security at the labs that worked with anthrax.

Over the past few weeks, the FBI has cast about widely for tips from the public, leading to speculation that the investigation was stalled. The bureau and the U.S. Postal Inspection Service sent a flyer asking for tips to every postal customer in New Jersey, and the FBI e-mailed a similar request to more than 40,000 microbiologists.

But interviews with investigators indicate that the attempt to shake loose tips represents only one track in the investigation. While it has been known for months that the strain of anthrax used in the terror attacks is the so-called Ames strain, scientists believe careful analysis will reveal slight genetic differences between the specific Ames variant used in the terror attacks and the variants kept by different laboratories around the world. Scientists could then create a kind of family tree showing which labs hold strains that are most closely related to the one used in the terror attacks.

The FBI has also commissioned tests that look at other biological properties of the bacterium and analyze the chemicals in the powder sent in the mailings. As many as 10 different laboratories are conducting these analyses, said a senior FBI agent.

The FBI has been extremely secretive about the progress of the genetic analysis of the anthrax, when it might be completed, and who is conducting the work. It is known, though, that the Institute for Genomic Research, a nonprofit laboratory in Rockville, Md., recently sequenced the DNA of the anthrax bacterium recovered from the spinal fluid of Bob Stevens, the first victim to die in the attacks.

The lab, known as TIGR, compared the DNA of the anthrax found in Mr. Stevens to that of an Ames strain held by a British laboratory, the Centre for Applied Microbiology & Research. The British lab had originally obtained its Ames strain from the U.S. Army Medical Institute of Infectious Diseases at Fort Detrick, Md. Comparing the Stevens and British samples, the TIGR scientists located small differences, but they have declined to elaborate.

In addition, Northern Arizona University, which holds the world's largest collection of anthrax strains, has been using a different method to compare the DNA of various strains. That method, developed by Prof. Paul Keim, is very similar to the way that police forensic labs examine the DNA of a person suspected of committing a crime. In both cases, scientists compare only specific sections of DNA known to mutate frequently.

Early on, the Centers for Disease Control and Prevention used Prof. Keim's method to determine that all of the bacteria used in the separate terror attacks were the Ames strain. However, the CDC looked at only eight sections of anthrax DNA, so its analysis was too superficial to pick up subtle genetic differences. Prof. Keim, who declined requests to be interviewed for this article, has said that he can examine about 50 separate stretches of anthrax DNA, making his tests far more sensitive. In addition, researchers from Los Alamos National Laboratory have identified 17 other DNA markers, called "single nucleotide polymorphisms," that can help distinguish different samples of anthrax.

But researchers are trying to make their tests even more sensitive, and that is taking time. Getting a rough draft of the genetic sequences can be done quickly, but ensuring that the sequence is reliable takes much longer. Then, researchers have to determine what new regions are useful for distinguishing among different samples.

To make the match, the FBI has obtained or requested anthrax from every lab in the U.S. that it knows worked with the Ames strain, according to the senior law-enforcement official. But a senior scientist at one domestic lab, who did not want to be identified, said that the FBI had not asked for samples. Also, a spokeswoman for the Canadian Defense Establishment in Suffield, Alberta, said, "We have not been approached officially or unofficially for any anthrax samples by any entity of the U.S. government."

Even if genetic testing could narrow down the number of labs likely to be the source of the terror anthrax, much work would remain to be done. "I don't think anyone is holding their breath that that alone will solve this case," a senior FBI investigator said. "It may not lead you to a person, although it will narrow the universe," said another high-ranking law-enforcement official. "Then from there, we can take some very affirmative steps."

Such aggressive steps aren't possible now, said FBI agents, because every lab that ever possessed any variant of the Ames strain of anthrax -- and all of the people who ever had access to those labs -- are potentially suspect. "It's too broad a focus," said the official.

Investigators acknowledge their approach may not work. Access to anthrax was "absolutely so lax," as one senior FBI agent puts it, that even if the lab is identified, it may not be possible to discover where the terror strain was sent or who had access to it. At Dugway Proving Ground, a large military facility in Utah currently under investigation, a former scientist said security was slipshod. "Somebody could have walked out of a hot area with a couple of spores in a briefcase or lunch pail," he said. Officials at Dugway declined to comment.

Biological thievery can be a problem no matter how tight the security. Chemical or nuclear stockpiles can be accurately inventoried. But biological agents grow, so a thief could steal a few spores of anthrax and they would never be recorded as missing. The terrorist could then use those stolen spores to grow huge colonies of the bacterium.

-- Antonio Regalado contributed to this article.