Timeline for determining source of 2001 anthrax attack released

Dr. Jacques Ravel of the Institute for Genome Sciences at the University of Maryland School of Medicine and the USAMRIID have released the timeline for determining the source of the anthrax letters from the 2001 attacks.

The timeline, which was first published in Saturday’s Washington Post, illustrates how researchers and scientists at the Institute for Genomic Research and Fort Detrick worked together to determine the origin of the letters sent as part of the 2001 attack.

While FBI investigators concluded that Fort Detrick researcher Bruce Ivins was the culprit of the attacks, some critics believe that the search was not exhaustive enough to rule out other labs who could have perpetrated the crime, the Washington Post reports.

In fall 2001, scientists at Fort Detrick identified the powder in the letters as anthrax spores and grew additional colonies from the spores to determine the original strain. After 48 hours, the scientists observed differences in color and shape, which indicated four key identifiable mutations.

Two years later, TIGR scientists mapped out the DNA sequences of the four mutants and screened them against over 1,000 anthrax samples from around the world to find a source, the Washington Post reports.

By March 2005, FBI investigators were confident that the anthrax came from a flask labeled RMR-1029, which was in the lab of Bruce Ivins at Fort Detrick, but they continued to screen and rule out samples. By fall 2007, the investigators had determined that only eight samples had the four mutant strains together. All of those samples, they allege, came from Ivins’s flask. The FBI then concluded that Ivins had sent the contaminated letters.