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From: Dr Michael H Arnold OBE MA PhD (Whittlesford, Cambridge).
I attach my contribution to the forum debate on GM, A Plant
Breeder's Perspective.
Outline experience:
35 years' experience in plant breeding - 20 in Africa; 15
in the UK. Consultant to international organisations spanning
a period of 24 years, including 8 years as a member of the
Technical Advisory Committee of the CGIAR
The GM Science Review (First Report):
A Plant Breeder's Perspective
Over the years, plant breeders have routinely adopted new
techniques. GM technology will eventually be seen as a natural
continuation of that process, not as a fundamental change
in the breeding systems required to produce successful varieties.
Some of the least predictable aspects of genetic change are
those associated with genotype-environment interaction, where
the environment includes everything affecting gene expression
and phenotype success. This will not be changed by incorporating
GM technology.
Moreover, GM need not imply the insertion of genes of widely
different origin. There would be logistical advantages in
gene transfer within a single species by GM methods. They
would, for example, obviate the time-consuming use of the
generations of backcrossing and selection otherwise required
to transfer a single trait from a primitive variety or sub-species
to an elite genotype of the same species.
The conclusion that the fate of transgenic DNA is no different
from that of other introduced DNA, reinforces the inference
that there is no functional distinction between GM and non-GM
varieties. Hence, everything hinges on the screening necessary
to detect and eliminate unwanted, or unstable traits. In future,
as in the past, these routine tests must mirror those enforced
by regulatory authorities. However, the more exhaustive the
tests become, the greater the cost and the slower the rate
of producing new varieties.
On a global scale, both food supply and environmental conservation
depend on increased agricultural productivity. In this context,
the risks of not using new technology might well be greater
than the risks of releasing GM varieties, for which proof
of absolute safety can never be achieved. The Panel does not
analyse the possibilities of achieving a balance between these
two risks.
It implies that, historically, the regulatory tests for new
varieties have been inadequate. It recognises gene effect,
rather than gene origin, as the important criterion. The Report
does not make clear, however, why the Panel implicitly concurs
with the philosophy that regulatory control of varieties should
relate to the breeding system used in their development.
The Panel also implicitly accepts the ideology of organic
producers. In particular, it does not challenge the assertion
that organic crops differ from others in that they must be
protected from out-pollination or seed admixture - an impossibility
in practice, and a demand that runs contrary to the scientific
philosophy on which the report is based.
Mike Arnold
August 2003
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