Genetics is good for you

My Times column is on the risks of genetic
research and therapy:

Fifteen years after the first sequencing of the
human genome, the genetic engineering of human beings is getting
closer. Will that mean designer babies and the rich winning life’s
lotteries from the start? And will we ever stop this slither down
the slippery slope to playing God? My answers are: no, and I hope
not. Despite dire predictions, almost nothing but good has come
from genetic technology so far, and we’ve proved that we don’t slip
down such slopes: we tread carefully.

The current excitement is over gene editing. A precise way of
doing this, called CRISPR-cas9, is all the rage among the
white-coated pipette-users. Last week, Britain’s five leading
medical research bodies (one of which, I should declare, counts me
as a fellow, the Academy of Medical Sciences) issued a joint
statement supporting the careful use of the new technique on human
cells for research and possibly therapy. They even recognised that
there might one day be a justifiable demand to use the new
technique on embryos in such a way that the changes would be
inherited.

We have had bio-ethical worries about six times in the past four
decades. First, in the mid-1970s, the discovery of how to do
genetic engineering in bacteria led to agonised debates about the
risks of biological warfare and accidents. Scientists themselves
imposed a moratorium and held a conference to devise rules. Today
the technique is routinely used, has virtually never been misused,
and has saved or improved the lives of millions: diabetics, for
example, use human insulin made by bacteria genetically engineered
to include human genes. It turned out better than feared.

Second, in the late-1970s, the discovery of how to fertilise
human eggs in test tubes led to equally agonised debates about what
this might do to human reproduction — such as allowing people to
seek out highly prized human specimens to father or mother their
children. In fact, the technology is used not to help people have
other people’s babies, but to help them have their own. It has
largely cured a wretched disease — infertility — and made millions
happy. It turned out better than feared.

Third, in the 1990s scientists began to modify the genes of
plants. Opponents raised the prospect of horrifying risks to our
food and the environment. Yet trillions of genetically modified
meals have now been eaten by animals and people with zero health
problems. GM crops have cut insecticide use, raised yields and
delivered healthier foods. Today’s scandal is not the harm GM crops
have done, but the suffering they have not been permitted to
alleviate, thanks to irrational opposition. Even if you are still
worried, you must concede that so far it has turned out better than
feared.

Fourth, around the millennium, scientists developed techniques
to clone mammals and some of us found ourselves on talk shows
discussing when vain plutocrats would duplicate themselves or their
pets, and at what risk to morality. In fact, cloning has proved
helpful in only a very few laboratory settings, but aside from one
or two pretty harmless pet-cloning episodes, has not been used at
all for frivolous purposes. It turned out better than feared.

Fifth, scientists sequenced the human genome, identified
disease-causing mutations and began to offer pre-implantation
genetic diagnosis to avoid bringing people into the world with
conditions such as cystic fibrosis or Huntington’s disease. Critics
worried that people would use the technique to make designer babies
who were good at the piano or maths. Yet demand for such positive
selection has proved minimal, partly because identifying specific
genes for specific traits is hard — and misreads the way genomes
work — and partly because, again, it turns out that people want
children like themselves, not paragons. Besides, good education is
still a far better way of giving a child an advantage. It turned
out better than feared.

Sixth, scientists discovered how to use viruses to insert new
genes into living tissues to cure certain fatal diseases —
so-called gene therapy. Early trials in human beings using
retroviruses triggered cancer and were abandoned. But safer
lentivirus gene therapy has now proved capable of saving lives, such
as those of immune-deficient babies, and is being used in more than
700 different trials. It turned out better than feared.

The score so far is six-nil to the optimists, then. Diabetics,
IVF children, bees in GM crops, parents who carry cystic fibrosis
or Huntington’s disease, babies with severe combined immune
deficiency — all have benefited. It has been feasible to use
genetic techniques for biological warfare and designer babies for
decades now; and it has not happened.

As the reaction to early gene therapy failures illustrate, the
slopes are not slippery. We advance very carefully down them,
retreating if necessary and re-evaluating the issues at every
stage. People want to use these techniques to cure diseases, not to
do eugenics. Genetic knowledge has not undermined morality or
respect for human life. All this does not, of course, prove that
future techniques will not be abused, but it must count for
something.

The latest gene-editing technique is generating attention
because it is so much more precise and effective than previous ways
of altering genes. Its first use will probably be in gene therapy —
extracting T cells from a cancer patient, editing the cells’ genes
to fight the cancer and re-injecting them — but even this is a long
way off. Work on germ-line genes is even further away. Some
scientists are calling for a moratorium on even the experimental
use of CRISPR-cas9 on embryos until we have discussed all the
ethical implications.

That would be a mistake. As genetically modified plants have
shown, moratoriums are blunt instruments — easy to impose and
difficult to lift when it turns out they are doing more harm than
good, especially in the age of social media.

Experiments produce knowledge to inform debates. A good example
is the recent debate on mitochondrial donation, a technique
developed in the laboratory before being licensed for use in
patients, where it may soon prevent dreadful degenerative diseases.
When the ethical debate on its use happened, seven years’ worth of
experimental results were on hand to answer many of the questions
raised. A moratorium would have meant debating in ignorance.

We should always tread carefully, but we should take comfort
from the truly remarkable track record of genetic technologies in
alleviating more human suffering than we dared to hope, and
encouraging fewer bad outcomes than we feared.