Palo Alto
– A group of multi-national European scientists has used gene-splicing
techniques to create an extraordinary tomato. It boasts a deep purple skin
and flesh, and contains levels of antioxidants 200% higher than unmodified
tomatoes. When fed to highly cancer-susceptible mice, the tomatoes significantly
extended the mice’s lifespan.
These studies have received wide attention, but an equally momentous achievement
of genetic modification has been largely ignored for almost a decade. That
innovation is “Golden Rice,” a collection of new rice varieties
that is bio-fortified, or enriched, by genes that express beta-carotene, the
precursor of vitamin A, which is converted in the body, as needed, to the
active form.
Most physicians in North America and Europe never see a single case of vitamin
A deficiency in their professional lifetimes. But the situation is very different
in poor countries, where vitamin A deficiency is epidemic among the poor,
whose diet is heavily dominated by rice (which contains neither beta-carotene
nor vitamin A) or other carbohydrate-rich, vitamin-poor sources of calories.
In developing countries, 200-300 million children of preschool age are at
risk of vitamin A deficiency, which can be devastating and even fatal. It
increases susceptibility to common childhood infections such as measles and
diarrheal diseases, and is the single most important cause of childhood blindness
in developing countries. Every year, about 500,000 children become blind as
a result of vitamin A deficiency, and 70% die within a year of losing their
sight.
In theory, we could simply supplement children’s diets with vitamin
A in capsules, or add it to some staple foodstuff, the way that we add iodine
to table salt to prevent hypothyroidism and goiter. Unfortunately, neither
the resources – hundreds of millions of dollars annually – nor
the infrastructure for distribution are available.
Biotechnology offers a better, cheaper, and more feasible solution: Golden
Rice, which incorporates beta-carotene into the genetically altered rice grains.
The concept is simple. Although rice plants do not normally synthesize beta-carotene
in the endosperm (seeds), they do make it in the green portions of the plant.
By using gene-splicing techniques to introduce the two genes that express
these enzymes, the pathway is restored and the rice grains accumulate therapeutic
amounts of beta-carotene.
Golden Rice offers the potential to make contributions to human health and
welfare as monumental as the discovery and distribution of the Salk polio
vaccine. With wide use, it could save hundreds of thousands of lives every
year and enhance the quality of life for millions more.
But one aspect of this shining story is tarnished. Intransigent opposition
by anti-science, anti-technology activists – Greenpeace, Friends of
the Earth, and a few other groups – has spurred already risk-averse
regulators to adopt an overly cautious approach that has stalled approvals.
There is absolutely nothing about Golden Rice that should require endless
case-by-case reviews and bureaucratic dithering. As the British journal Nature
argued in 1992, a broad scientific consensus holds that “the same physical
and biological laws govern the response of organisms modified by modern molecular
and cellular methods and those produced by classical methods.... [Therefore]
no conceptual distinction exists between genetic modification of plants and
microorganisms by classical methods or by molecular techniques that modify
DNA and transfer genes.”
Put another way, government regulation of field research with plants should
focus on the traits that may be related to risk – invasiveness, weediness,
toxicity, and so forth – rather than on whether one or another technique
of genetic manipulation was used.
Nine years after its creation, despite its vast potential to benefit humanity
– and a negligible probability of harm to human health or the environment
– Golden Rice remains hung up in regulatory red tape, with no end in
sight. (Cancer-preventing tomatoes, take notice.)
By contrast, plants constructed with less precise techniques such as hybridization
or mutagenesis generally are subject to no government scrutiny or requirements
(or opposition from activists) at all. That applies even to the numerous new
plant varieties that have resulted from “wide crosses,” hybridizations
that move genes from one species or genus to another – across what used
to be considered natural breeding boundaries.
Judith Rodin, the president of the Rockefeller Foundation, announced last
October that her organization will provide funding to the International Rice
Research Institute to shepherd Golden Rice through national regulatory approval
processes in Bangladesh, India, Indonesia, and the Philippines. This is good
news, but what is really needed is a multi-faceted, aggressive reform of the
regulatory process so that all new genetic constructions will have a chance
to succeed.
In an April editorial in the journal Science , Nina Fedoroff, an
eminent plant geneticist who serves as senior scientific advisor to US Secretary
of State Condoleezza Rice, wrote: “A new Green Revolution demands a
global commitment to creating a modern agricultural infrastructure everywhere,
adequate investment in training and modern laboratory facilities, and progress
toward simplified regulatory approaches that are responsive to accumulating
evidence of safety.
The Golden Rice story makes it clear that we do not yet have the will and
the wisdom to make that happen.
Source:
Henry Miller(2009). A squandered golden opportunity. Project Syndicate
(http://www.project-syndicate.org:80/commentary/miller6)
This article is reproduced with the permission of the author.
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