Re: Cell DNA versus body DNA quantity?

On Feb 24, 2:57 am, topmind <topm...@xxxxxxxxxxxxxxxx> wrote:
I'm curious about something that maybe a specialist here can answer.
What percentage of animal DNA is devoted to cell-level issues versus
body-level (super-cellular) issues? I realize there is some overlap,
but a rough estimate would still be satisfying.

It may help answer the question about why it has seemed to take a
relatively long time in Earth's history for multicellular life to form
and thrive. Cells may have needed to be sufficiently complex and
flexible before multicellular life was competitive.

Thanks

-T-

Sorry for the double post, I hit the wrong button.

There is considerable overlap. You also have to consider that most of
the genome seems to just take up space, so we might just consider
known genes. We will miss a fraction of noncoding DNA that is
involved in gene regulation for multicellular purposes. Prokaryotes
that don't do much more than form colonies and biofilms have on the
order of 1000 genes. Simple eukaryotes like yeast may not form
complex multicellular structures, but may have an order of magnitude
more genes (around 10,000), related fungi may form fruiting bodies and
still only have around 10,000 genes. Infact humans still have the
same order of magnitude number of genes (around 30,000).

So if there is some kind of break point it occurred at around an order
of magnitude more genes that your usual bacterium needs to be about
the most successful lifeform on the planet.

There were probably enough genes to get the job done long before the
means to get them to all work together to produce a multicellular
organism evolved.

Ron Okimoto

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