Tuesday, August 05, 2008

This from the Smithsonian?

The Smithsonian has a "blog" called "The Gist." A recent item about the dinosaur "meat" controversy written by Hugh Powell has the following two sentences,

"They cracked the bone in half to make it fit, and Schweitzer noticed a goopy residue on the 65-million-year-old insides of the bone (see the Smithsonian story). Then this April, Schweitzer and her colleagues isolated a protein called collagen from the sample, analyzed it, and found striking similarities to the collagen of modern birds."

I am very disappointed in this misrepresentation of Schweitzer's work. There are at least five errors of fact;

The femur, MOR-1125, was broken due to weight issues not size, Schweitzer was not at the site, and the organic residue was not "goopy" or even visible to the naked eye. The article published in Science last April, Organ et al, had not "isolated a protein called collagen." Rather, they used BLAST searches to attempt a phylogenetic tree for prior data. These earlier data were still not the "protein called collagen." Rather, Asara et al (2007) analyzed seven small peptide fragments they attributed to collagen. They may or may not have been correct in that attribution. The fragments, even if from collagen, are from very highly conserved regions of that molecule.

"Protein Sequences from Mastodon and Tyrannosaurus Rex Revealed by Mass Spectrometry" (John M. Asara, Mary H. Schweitzer, Lisa M. Freimark, Matthew Phillips, Lewis C. Cantley, Science 13 April 2007: Vol. 316. no. 5822, pp. 280 - 285

"Molecular Phylogenetics of Mastodon and Tyrannosaurus rex" (Chris L. Organ, Mary H. Schweitzer, Wenxia Zheng, Lisa M. Freimark, Lewis C. Cantley, and John M. Asara, Science 25 April 2008 320: 499)

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