Sunday, August 3, 2008

What are these people talking about? (Part 4)

I am referring to this story.
It states that:
"The DNA linked the anthrax used in the mailing to a flask used in Bruce Ivins' lab at the U.S. Army Medical Institute of Infectious Diseases, said the source, who was not authorized to speak publicly about the case."
Can you identify the part of this phrase that tells the reader that the writer has no idea what they are talking about? It is this part: "DNA linked the anthrax used in the mailing to a flask." Not only do flasks not have DNA, but they are used, sterilized, washed and resterilized. I doubt a culture started in 2001 would still be sitting in a flask this many years later. What (I think) they mean to say is that the DNA matched the DNA of a strain that Bruce Ivins had a stock of in his lab. Alternatively, if the labs at USAMRIID were searched and samples were taken, then maybe they mean that the DNA from the letters matched a sample of culture taken from a flask in Ivins' lab.
I know this is picky, but how am I supposed to know what else the writer did and did not interpret correctly when they clearly do not have the science background needed? Besides, this is not the first thing I've read since Friday that wasn't accurate.

This story, released by the AP contains a couple of strange staements and I am not sure what to make of them. The statements are as follows:
1. "Although the Army lab where Ivins worked had long been on the FBI's radar, scientists were unable to pinpoint the specific strain used in the attacks until about a year ago."

The B. anthracis strain isolated from a victim of a recent bioterrorist anthrax (Bacillus anthracis str. A2012) was sequenced and a paper describing the unique genetic markers associated with strain A2012 appeared in the journal Science in 2002. Furthermore, you can find the nucleotide sequnce in the NCBI database.

2. "The new genome technology that tracked down Ivins was either not available or too expensive to use often until about three years ago."

I don't know what new genome sequencing technology would be needed for a strain that is already sequenced. Any thoughts?


chall said...

I'm not sure either. I thought you could get DNA from the spores but maybe it's trickier than I thought... hm, I always assumed they got the DNA from the letters and then ran a comparison sequence with the known markers for the dozen or so known strains in the labs in US and Russia.

THanks for blogging about this since I found it very annoying to read yesterday... the paper and the news story that is.

microbiologist xx said...

You're right. You can get DNA from spores.
I am glad someone enjoyed my posts. The blog turned out to be a great outlet and for once I wasn't racking my brain trying to think of a topic.

Anonymous said...

If the technology is only a couple years old, maybe they are referring to resequencing arrays? I agree with Chall and Microbiologist, the news stories have been very aggravating.

Thomas Joseph said...

Perhaps they performed some sort of SNP (MLST), MLVA analysis or a mixture of the two? It's possible they sequenced multiple strains from a multitude of the victims, aalong with the genome of his lab strains (all of which should have been registered in a Federal database).