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July 26, 2000


Super Fish, GMO Detection Course


AgBioView - http://www.agbioworld.org, http://agbioview.listbot.com

Date: Jul 26 2000 22:35:43 EDT
From: Malcolm Livingstone
Subject: fish

Dear All,

Re: Andrew Apel's message on transgenic fish.

Andrew I read the article in Nature by the two scientists involved and
wrote to one of them with a few questions. I am not an ecologist or
someone who is an expert in animal group dynamics so I don't feel sure of
my ground on this one. I asked the following questions but have yet to
receive a reply. Perhaps somebody on this list can help answer them.

If transgenic salmon grow more quickly than wild salmon doesn't this mean
that they will require a greater food density to survive? If so isn't it
also the case that wild salmon are superbly adapted to their environment
and probably use every bit of food available to them? It seems to me that
any competitor in a stable food chain is likely to be at a major
disadvantage. Of course feral invaders may become pests (common problem in
Australia) if they are better adapted to compete with the native animals
food supply. However in this case the potential invader is not a true
feral but a different, and maybe less efficient, "variety" of the same

Also what is the relationship between growth and mating. Do these salmon
mate at a particular time of the year (I expect they do)? If so, do the
transgenic salmon remain fertile and ready to mate after they reach
maturity? It seems to me to be a benefit if most of these fish die before
they reach sexual maturity. Any accidental release into the wild would
have to be large and at the right time of year to produce a Trojan gene
Any transgenic offspring would have to compete not just at breeding time
but through the whole lifecycle of the fish. Unless there is some untapped
food source that will only be available to larger fish (and there may well
be) then I can't see how they would survive. If they were able to survive
then so would the species. I know that insects are often controlled by the
release of sterile animals but this has to be done at breeding times and is
only partly successful. I don't think any insect species is threatened by
this activity. I realise that this is only theory and there is a strong
case for more empirical evidence. I would be very surprised if these GM
fish are competitive in the wild. I wish you all the best in future
experiments and look forward to the results.

Yours Sincerely

Malcolm Livingstone
CSIRO Tropical Agriculture

The views expressed in this letter are my own and in no way reflect those
of my employer.

Subj: Re: Superfish
Date: Wed, 26 Jul 2000 6:04:54 PM Eastern Daylight Time
From: EEntis@aol.com

The recent and continual controversy over how "superfish" will affect the
population of wild, natural fish of the same species is largely the result
of a hypothesis published by Muir and Howard in PNAS (11/23/99) and
called by them the "Trojan Gene Effect".
Their hypothesis is based on two and only two assumed variables: if
transgenic male fish are larger than their cohorts at sexual maturity they
will have a 400% greater mating success with females than their less well
endowed brethren; and if their offspring are 30% less viable (able to
reach sexual maturity) than non-transgenic offspring, the combination of
the two factors will lead to a total extinction of the wild population
within 40 generations. Their result was achieved by running a set of
relatively simple
equations showing that as the transgene gets fixed in the wild population
through continual gene introgression, it simultaneously reduces the entire
population in an ever increasing downward spiral by reducing overall
fitness. The salient facts and problems with this hypothesis include the
(1) it is not an empirical study, it is in fact only a hypothesis based on
two out of presumably hundreds of variables which determine the size of a
wild population of animals. This is akin to forecasting the weather based
solely on whether it is day or night.
(2) The size of the variables underlying the hypothesis (e.g., 400%
greater mating success) was based almost exclusively on the presumed
behavior of medaka, a small laboratory fish, without any empirical
observations on this issue. In fact, at the time the article was written,
the authors acknowledged that they had generated transgenic medaka, but
that they were not larger than their non-transgenic cohorts at sexual
maturity and thus they could not test their basic assumption. In fact,
they did not attempt to validate the
assumption of size:mating success even by using standard medaka.
(3) A critique which has been brought up on several occasions is the
query: if size is the critical factor for mating success, at least among
medaka, why aren't all medaka the size of whales?
(4) The relevance to a commercial species, such as salmon, is dubious: it
is well known that male salmon mate at sizes ranging from a few ounces
and inches (precocious males) to tens of kilograms. Their is no set
"mating size" for these animals.

In numerous conversations and e-mail exchanges I have had with one of the
authors, Dr. Muir, he acknowledges the limitations of the hypothesis and
is in fact attempting to do an empirical study using tilapia as a model,
and intends to broaden the number of factors that will be taken into
account. Regardless of the eventual outcome of these studies, the central
point is that Dr. Muir admits that if transgenic males are not larger than
non-transgenic counterparts at sexual maturity, then his hypothesis is not
relevant. In the case of "superfish" - the rapidly growing Atlantic salmon
produced by my company, Aqua Bounty Farms, multiple generations of
empirical evidence show that our fish, although they reach full adult size
very quickly, are in fact slightly smaller than their non-transgenic

Their growth rate which is very rapid in early life slows down, and
coupled with the fact that these fish reach sexual maturity sooner than
their standard siblings, at which time growth rates become all but zero,
has led to consistent observations that their mean body weight is somewhat
less than in the other fish.

Elliot Entis
Aqua Bounty Farms

Date: Jul 27 2000 07:44:25 EDT
From: C. S. Prakash"

(Trieste, Italy, October 2-6, 2000).

A theoretical and practical course has been jointly organized by Techna
Srl. and Bio-Rad Laboratories Srl. The course will be held in the ICGEB
laboratories in Trieste and
is directed to scientists and laboratory technicians involved, in private
or public sector, in food and feed analysis. The training will be managed
by scientists from the University of Greenwich (UK) and the Istituto
Zooprofilattico Sperimentale (Institute for Animal Disease Prevention) of
Perugia (IT).

STRUCTURE: The course will be organized in two sections:
a) First Section: October 2-4: Introduction to qualitative PCR and
immunochemical methods;
b) Second section: October 4-6: Quantitative and "Real-Time" PCR (this
section is exclusively directed to participants with experience in
molecular biology).

SUBSCRIPTION FEE: ITL 2.000.000 for each section or ITL 3.500.000 for the
whole course (1 US$ is about 2065 ITL - Italian Lire); it includes safety
insurance, social events, handouts and reports.

CLOSING DATE FOR APPLICATIONS: September 15th, 2000. Registration is
limited to 20 participants. A minimum number of participants will be
required for the course to take place.

Tecna Srl, Training Department, Tel. +39-040-3755341,
fax +39-040-3755343, mailto:techservice@tecnalab.com,
Further info will be available on the Tecna web site at:

GRANTS: A limited number of grants will be available for scientists from
ICGEB Member Countries. These grants will cover subscription fee,
accommodation, meals and incidentals for the duration of the course;
travel is NOT funded. Applications for grants should be sent, with
attached CV, directly to:
ICGEB Programme and Training Unit, Padriciano
99, 34012 Trieste, Italy. Tel: +39-040-3757333; Fax:
+39-040-226555; mailto:courses@icgeb.trieste.it

Note. ICGEB is looking for Sponsors / Co-sponsors / Contributors in order
to support the widest participation to biosafety courses. Interested
organizations may wish to
contact the ICGEB Biosafety Unit (mailto:biosafe@icgeb.trieste.it)

- - -

The report of the Florence Workshop: "Biosafety2. Advanced
Research and Procedures: Case Studies for Designated
Experts" (3-8 April 2000) is available in PDF format at:

- - -

The last activity report of the ICGEB biosafety unit is
available (in HTM and PDF format) at the following URL:

The International Centre for Genetic Engineering and Biotechnology (ICGEB)
is an autonomous, international, intergovernmental organization formed by
62 signatory
countries of which 43 are full Member States. The Centre is dedicated to
advanced research and training in molecular biology and biotechnology. The
mandate of the ICGEB is to promote the safe use of biotechnology
world-wide and with special regard to the needs of the developing world.
Further information on the ICGEB could be found on its web pages at