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Re: Rconstructing DNA (was Re: Dino-fuzz found in amber?)

Surely it is predictive. In a probabilistic manner, but predictive.

Yes. We could search the GenBank to see if there are sequences that
could be used.


Roberto Takata

On Mon, Sep 19, 2011 at 7:10 PM, Sam Barnett <sam.horus@gmail.com> wrote:
> Is it predictive? Can I use this method to accurately infer the DNA of a
> given domestic dog breed if I have two more recent breeds' DNA and that of a
> wolf?
> On Monday, September 19, 2011, Roberto Takata <rmtakata@gmail.com> wrote:
>> On Sun, Sep 18, 2011 at 3:53 AM, Tim Williams <tijawi@gmail.com> wrote:
>>>  What then? What can you do with it?  You'll never know if you're right,
>>> because
>>> we're never going to find _T. rex_ DNA.
>> What you can do with *paleontology*? You never will find courtship
>> behaviours, colours of the most (oh wait!)...
>> The methodology is sound enough to molecular biologists use this
>> techniques and reconstitute ancestral sequences.
>> The rationale is basically the same as the morphological phylogenies.
>> We can infer that the most recent common ancestor of protostomes and
>> deuterostomes had bilateral simmetry. There are many characteristics
>> that are inferred for the Urbilateria.
>> Even for Cenancestor or LUCA.
>> -----
>> Well lets take Crocodylus niloticus peptide fragment (NADH
>> dehydrogenase subunit 6, a mitochondrial protein), the first 10 aa
>> residues are: MNINRWLFST
>> And for Gallus sonneratii for the homologous protein fragment: MTFINRWLFS
>> Croc:   MN  INRWLFST
>> It seems that a codon is missing in croc (or was inserted in Gallus
>> evolution).
>> For the modified vertebrate mitochondrial genetic code we have for croc:
>> M -> AGA/GTG
>> N -> AAT/C
>> I -> ATT/C
>> N -> AAT/C
>> R -> CGN
>> W -> TGA/G
>> L -> TTA/G; CTN
>> F -> TTT/C
>> S -> TCN
>> T -> ACN
>> The G. sonnerati DNA sequence is: GTG ACC TTC ATC AAC CGA TGA CTA TTC TCA
>> So we see the seventh codon of C. niloticus it corresponds to the
>> eighth codon of G.sonnerati, which is CTA. So the croc codon probably
>> is CTN. And in the actual DNA sequence it is CTT.
>> And croc/bird split is much older than T-rex/bird split.
>> []s,
>> Roberto Takata