SELLING an idea to the world is an art in itself. Let the seller beware: no
matter how good or scientifically sound the notion, if it is not pitched right
it may fall on stony ground. Worse still, it may provoke outright hostility.
One idea to arrive this week, in the form of a patent application, is a DNA
chip from British company Genostic Pharma
(see p 4). The application, while not
a press release, gives clues to the company鈥檚 thinking and it raises some
important pointers for hopeful biotechnology companies about to launch a new
product.
DNA chips are wafers to which are attached probes made of short fragments of
selected genes. Squirt people鈥檚 DNA over the chip and if they have one of those
genes, it locks onto the relevant probe, which lights up in response. DNA chips
are seen as critical for making sense of the telephone books full of information
we鈥檙e about to receive about the human genome. Their most obvious use is for
diagnosis. They will show if somebody carries the gene for, say, cystic fibrosis
while ignoring the 99 999 others.
Advertisement
Most DNA chips search out a single disease. Genostic鈥檚 idea is to create a
wide-ranging genetic profile in one go. Its chip will carry probes for four or
five variants of about 2500 genes. It is a bold idea: one that makes you wonder
why nobody thought of it before. But even apparently inevitable ideas come with
problems attached.
Genostic proposes that the chip should be used to bring genomics into
everyday medical practice鈥攁 laudable aim. But it then lets itself down by
suggesting that the chip could be used for 鈥渟electing applicants for
employment鈥�. Hands up anyone who agrees with that? Bill Clinton certainly
doesn鈥檛. Last month, he banned US government agencies from using genes when
selecting employees.
Then there are the chosen genes. These are for disorders ranging from cancers
to heart disease and dementia to sexual dysfunction. Yet all the geneticists
contacted by New 杏吧原创 doubted that we yet know which genes are
important in such disorders. Genostic agrees that its choice of probes needs to
be 鈥渧alidated鈥�, so it鈥檚 difficult to be confident that the company has found all
the right genes.
The validation process for matching genes to diseases is no simple task. One
way to do it would be to take the profiles of large numbers of people and follow
them for many years to see which disorders they develop. Another would be to
compare profiles from people who have the target conditions with those from
people who don鈥檛. Either way, it will take time.
Another issue is why Genostic chose to put probes on its chip for behavioural
traits鈥� including 鈥渋ntelligence鈥�. This is a controversial addition indeed.
Many ordinary people will be horrified to hear that doctors are checking their
mental abilities. The company has said that if some genes are too hot to handle,
it will remove them from the chip.
Assuming Genostic validates its probes, doctors and the public will have to
come to terms with the flood of information the chips will produce. Already, we
know that people need careful counselling about single-gene disorders, such as
cystic fibrosis.
Many of the disorders covered by Genostic鈥檚 DNA chip, such as heart disease,
will be influenced by many genes, not to mention environment. What sensible
advice will gene testing provide for these disorders? And let鈥檚 not forget that
doctors will be giving patients results from chips about a whole raft of such
conditions.
Dealing with genetic information, of course, is not a problem that鈥檚 specific
to DNA chips. It is inevitable as we learn more about our genetic makeup. But
the chips bring these issues into sharp focus and highlight the need for
sensitive thinking about genetic testing.
So how should Genostic be persuading a sceptical world of the value of its
chips? They are without doubt a useful research tool and the validation studies
themselves will throw up valuable information. Even if the genes that Genostic
has chosen are not implicated in the diseases it thinks they are, they may turn
out to be important for other disorders. Who would have thought, for example,
that variations in a gene for the blood protein apolipoprotein E would turn out
to be risk factors for Alzheimer鈥檚 disease?
Only once these studies are done will Genostic鈥檚 vision of a tool for
everyday clinical practice emerge from the surrounding fog. Push that vision,
with all its incumbent controversies, too soon to a naive and anxious public and
the result could be disaster. Just ask Monsanto about the meaning of
鈥渂补肠办濒补蝉丑鈥�.
