On Thu, 15 May 2003 13:01:55 +0200, Tim
wrote:
On Thu, 15 May 2003 11:12:40 +0100, Stephen Howard
wrote:
On Thu, 15 May 2003 10:56:30 +0200, Tim
wrote:
The difference being that "pick-n-mix" cross breeding transfers any
number of unknown genes, whereas a GM organism would have only a very
few, well known, genes transfered.
The difference between the sledge-hammer and scalpel approaches. Which
one is best ?
You see...there it is again... 'any number of unknown genes'.
Precisely my point. If there are 'unknown genes' then there are
unknown properties.
I don't quite see what you're aguing about here. Plant breeders do this all
the time.
Yes, they do - and if it works it works because it's a natural process
- it's bringing nature to nature, and all that that encompasses.
In other words, nature sorts it out in its own inimitable fashion.
Ever tried crossing a Leek with a Honeysuckle? Had any success?
Most likely not, because somewhere down the line evolution said
'uh-huh, no can do'.
That's a very simplistic view of evolution, isn't it?
You and I know there's more to it than that.
Simplistic it may be, but it is wrong?
It's interesting that you regard the incredible intricacies of natural
selection as being akin to a 'sledgehammer approach'.
I didn't express myself very well there, sorry. The sledgehammer approach
was meant to be applied to artificial breeding, which to a great degree
side-steps natural selection, and replaces it with human, artificial
selection.
I quite agree there - but in that case we act as mere matchmakers.
You can bring together two people who might not normally meet, but
that doesn't mean they'll get on with each other. And if they do get
on, perhaps it will be in unexpected ways.
The point here is that there's a lot of interplay that goes on behind
the scenes that I'm not convinced we fully understand as yet.
In reality I'd say it's more like two buckets of sand being mixed up. So,
what would be less likely to produce any great unexpected changes - mixing
2 buckets of sand, or just swapping a couple of grains over?
But sand is inert - it won't evolve, mutate or otherwise change its
properties. It's a poor analogy for a gene.
Natural selection can only work on variety. This variety is created by
mixing and remixing the available genes. A little ramdom input from
occasional mutations adds some novel variation as well, but it's a small
part. Mix everything up and see what survives. A simplification, perhaps,
but that's the backbone of the theory of natural selection.
Yes, I understand that - and by the same token that doesn't preclude a
mutation from wreaking havoc - but on the whole the system appears to
function very well indeed.
I rather feel that nature's methods make your scalpel look like a blunt
sword.
It's not MY scalpel. If you just fuse germ cells, as happend in the
development of modern wheat strains for exaple, who knows what you're
making? Reduce the number of changes being made, and you have more chance
of finding any problems.
It's that element of 'chance' that's the problem, you see.
It's just not good enough to say 'hey, we can dabble with this and
tweak that.... and hope to hell we catch any adverse effects'.
And just when d'you stop looking?
Nature builds on balance - this is why folks who consistently use
pesticides get locked into using them, they create their own
imbalances.
I can't agree with you more. Bit hardly relevant to the topic is it?
The balance of nature isn't relevant to transgenic plants??
Nature doesn't stop working simply because mankind pitches
in with a few crude attempts at tipping the scales - if you leave a
hole, nature will fill it... and not necessarily to your advantage.
Without those unknown genes, how many holes will you create, and what
will fill them?
But we're not talking about building organisms from scratch, where there
would be huge great holes all over the genome. We're talking about taking a
whole genome and adding/changing just one or two genes.
So you have smaller holes, is all. And small holes have an annoying
habit of becoming large holes.
And as you well know, the gene stands at the tip of the inverted
pyramid and interacts all the way up and through the plant's whole
structure...which then interacts with other organisms in the same
fashion... and so on ad infinitum. I'm not convinced that anyone is
fully aware of just what the knock-on effects might be.
Regards,
--
Stephen Howard - Woodwind repairs & period restorations
www.shwoodwind.co.uk
Emails to: showard{whoisat}shwoodwind{dot}co{dot}uk