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Re: Dino-fuzz found in amber?



Well, I'm not wrong because I didn't write that THE sequence could be reverse 
engineered, I wrote that "sequences can be reverse engineered", which is 
plural, and is in keeping with what you've written. 

If you're so eager to pounce on stuff at least please read it carefully.

On Sep 15, 2011, at 3:33 PM, Erik Boehm wrote:

>>>> Right, Mary Higby Schweitzer's work was on the amino acid sequences of 
>>>> proteins, from which DNA sequences can be reverse engineered.<<<
> 
> Wrong.
> You cannot get the DNA sequence from the protein sequence.
> There are 64 possible codons for 20 amino acids.
> 
> You can generate *a* DNA sequence that would produce that amino acid 
> sequence, but you cannot generate *the* DNA sequence that produced those 
> proteins (at least not with any certainty)
> Moreover, the interesting stuff like regulatory regions cannot be predicted 
> from the amino acid sequences.
> 
> Additionally, the "genetic code" mapping 64 codons to 20 amino acids is not 
> uniform in life - there are variations of it - although it is highly unlikely 
> that dinos used a different code than the one found in birds and mammals.
> 
> However, if we were to get an amino acid sequence from some microbe that 
> lived billions of years ago, we couldn't even generate *a* DNA sequence that 
> would have worked in the organism to produce the observed amino acid sequence 
> with any certainty.

Jason Brougham
Senior Principal Preparator
American Museum of Natural History
jaseb@amnh.org
(212) 496 3544