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Sunday, October 17, 2010


"Interestingly, mutations were observed at a frequency dependent on display valency".

This is a quote from a paper that was published regarding some work that I performed. It is a confusing statement. A phage library was made with 7 random amino acids stuffed into a 20 amino acid peptide. Does the statement mean if there were 8 random amino acids that there would be more mutations?

Like Feynman said, we should report everything we do, not just the things we want people to believe. Phage libraries can be made from simple oligo sythesis samples from companies like Invitrogen. There were ten vials of DNA preparations that came from several oligo orders from Invitrogen. One of the oligo orders came in with all phenylalalines where random nucleotides were suppose to be. Not a mutation, but a mistake at Invitrogen. There was one oligo that gave the best results. It was used to make 5 DNA preps that were inserted into our phage vector. Only 2 of these preps gave the results we needed to get the library done. 90% of the library come from the first prep.

The other oligos should have been the same but we humans were doing work with them. The "mutations" that the paper mentioned disappeared when a new oligo was ordered. However, new "mutations" came with new DNA. It is a normal occurrence in cloning man made DNA into vectors. The fidelity of the DNA insert was pretty good actually. The only thing interesting is how ignorant the authors of the paper and the editors of the journal were to this fact.

Perhaps someone else should have tried to reproduce the work. That would serve everyone interested by demonstrating that the papers "mutations" claim was not only wrong, but a non-science claim.

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