[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: Dino-fuzz found in amber?



>>> 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.