The facts: The controversy surrounding the study
meant that decision of the editor of the Lancet to publish the data
was not an easy one. One of the peer reviewers who requested that
his name be kept secret said it was wrong to publish the study as
Pusztai's conclusions were wild speculations. A statistics specialist
- also involved in the peer review process - added that the statistical
methods employed were inadequate and the analyses quite simply wrong.
Another scientist, Martin Chrispeels, agreed: " This isn't science.
It wouldn't be published in a serious plant biology journal. Their
conclusion is not correct." Another of the six peer reviewers -
usually there are only two or three - John Pickett, even went on
public record to say it would be a very sad day if such a respected
journal were to ignore the advice of its own peer reviewers.
Why, then, did Richard Horton, editor of The Lancet, go ahead with
publication against his reviewers' recommendation? He says why in
the same edition under the heading "Genetically modified foods:
"absurd" concern or welcome dialogue?". His perspective is the viewpoint
of the concerned (British) public. He argues that " risks are not
simply questions of abstract probabilities or theoretical reassurances.
What matters is what people believe about these risks and why they
hold those beliefs."
Horton sees the gap between science and society getting wider and,
in the post-BSE age, has hit the nail squarely on the head with
this assessment. Science is under growing pressure to legitimate
itself and is facing an enormous communication deficit which it
studiously ignores and appears unequal to deal with. Horton backs
up his views with statements from representatives of industry and
science who have eyes only for the fact that biotechnology in Europe
is lagging behind and tend to attribute public concerns to pure
ignorance. However, Horton also insinuates that he shares his reviewers'
opinion of the scientific reliability of Pusztai's data. Nevertheless
he pleads for debate, saying that forever attacking the critics
instead of including them in the discussion process will only increase
public mistrust in scientists and science.
In spite of the earlier mentioned but obviously non-existing symptoms
and signs of the rats' diseased state - they had neither brain nor
liver damage, nor were they immune suppressed - Pusztai and Ewen
nevertheless come to the conclusion that the differences in small
intestine histology in the rat groups on different diets (potatoes
with added GNA and GNA-lectin-producing potatoes) could be the results
of transformation of the potatoes with the GNA gene. But the data
are completely inconsistent. One time Pusztai observes an effect
in a comparison of the cooked potatoes, another time in the raw
potatoes.
This seems to be a case of too many effects getting on top of each
other. Harry Kuiper points out an elementary methodological error
in his article entitled "Adequacy of methods for testing the safety
of genetically modified foods" published in the same issue of The
Lancet. He rightly criticizes the fact that Pusztai and Ewen failed
to discuss the possible differences in composition (macronutrients
and micronutrients, toxins) of the transgenic and parent potato
lines - whereas, as Kuiper states, " Pusztai has released some of
these details on the internet.
These details indicate that the content of starch, glucose polymers,
lectin, and trypsin and chymotrypsin inhibitors in GM potatoes differed
from that of the parental line." Pusztai himself therefore provides
evidence of the lack of substantial equivalence of the two lines
and, by the same token, of the lack of comparability in his feeding
studies. Another problematic issue is the excessively low protein
content in the potatoes of only 6%. A healthy diet should contain
approximately 15% protein.
On balance, too many effects and uncertainties cloud the sparse
data, the interpretation of which necessarily enters the realm of
speculation. To finish, Pusztai uses his publication as a forum
for general criticism and uses his data as a basis for making a
sweeping generalization in respect of transgenic plants in general:
The possibility that a plant vector in common use in some GM plants
can ... exert powerful biological effects may also apply to GM plants
containing similar constructs, particularly those containing lectins,
such as soy beans. This statement - RR-soybeans are cultivated on
millions of hectares in the USA - is one that Pusztai certainly
cannot support from his weak data.
His comments are not just speculative, they are unscientific to
a high degree.Kuiper also discusses the safety of transgenic plants
in his article and reaches a more discerning conclusion, i. e. concludes
that the concept of substantial equivalence is an adequate principle
on the basis of which to test and demonstrate the safety of today's
generation of transgenic plants. He identifies a need for action
as regards future developments, however, stating that the second
generation of transgenic plants whose product quality has been optimized
in terms of protein or fatty acid composition also necessitates
adaptation of safety tests and development of new methods.
A fourth article in the same edition of The Lancet criticizes Pusztai's
basic idea of integrating Galanthus nivalis lectin (GNA) into plants
as a natural insecticide. Brian Fenton from the Scottish Crop Research
Institute - the institute Pusztai cooperated with - describes the
interaction of GNA and human cells as being inadequately understood.
He and his colleagues show in an experiment that - in contrast to
Pusztai's claims - GNA binds to human white blood cells and thus
has the potential to trigger biological effects. This is a very
subtle criticism of Pusztai's work, as the latter assumed that GNA
- unlike other lectins - is not toxic to the mammalian organism,
which is why he chose precisely this lectin for transformation of
his potatoes.
In publishing Pusztai's data, The Lancet afforded him the opportunity
of officially presenting his findings. However, the printed paper
is unscientific and in no way calls the safety of transgenic plants
into question. Nor does it go any way towards rehabilitating Pusztai.
Pusztai's data no longer need to be discussed on the quiet and nobody
can claim that information is being suppressed. The Lancet has certainly
taken a bold and unusual step, but lives up to its reputation for
good science by the simultaneous publication of another three articles
on the topic. Why shouldn't a scientific journal take on the task
of pointing out blatant deficits in communication and drawing attention
to the dwindling public trust in its country's scientists?
