All scientific progress brings changes. Weighing benefits against risks is particularly difficult in the life sciences. How do people decide between animal experiments and animal rights? Should pets be cloned? Or humans?
ALL progress in science and technology has an impact on people's lives. Often these effects are positive—antibiotics, computers and electricity have made our lives safer, easier and more comfortable. But inventions can bring suffering and injustice, such as nuclear war, pollution and road accidents. How do we decide what is the right and wrong use of science? These difficult choices lie in the realm of ethics.
Few of us would argue over the chemical formula of sulphuric acid, or the
right names for the bones in the human skeleton, but when it comes to ethical
questions there is often disagreement on what is "right". Views
on issues such as genetic screening and clinical
trials are affected by religion and culture. And what is
acceptable, changes over time. In 1967, many condemned the first heart
transplant as unnatural. But most people now accept these operations as
life savers. In 30 years time, will we happily accept the transplantation
of animal organs to humans?
Weighing benefits against risks can often provoke strong feelings, as with
the arguments over animal experimentation. Animals are used in three main
ways these days: in medicine, cosmetics and transgenics. Each raises different
questions about risk versus benefits.
Thousands of lives are saved every year through medicines and surgical
techniques that were first tested out on animals. Research into cancer,
mental illness and neurological disease such as multiple sclerosis—all
conditions for which there is a clear need for new treatments—rely
heavily on animal experiments. In this case, most of us agree that the
benefits in terms of reduced human suffering outweigh the inevitable suffering
inflicted on the animals. In 1990, for example, 3.2 million animals experiments
took place (Figure 1).
Figure 1
But a minority of animal experiments are carried out to test cosmetics and toiletries. Here the balance seems to tilt in the other direction. Some of these items are undoubtedly necessary, but should animals suffer just to bring a new kind of makeup or deodorant to supermarket shelves? Companies could instead be asked to use ingredients already known to be safe.
Transgenic animals, which carry genes from humans and
other species, can be used to test new treatments for diseases such as
sickle-cell anaemia. New drugs can be developed by creating transgenic
sheep and cattle that carry genes for human proteins that are produced
in their milk. Dolly, the cloned sheep, was created as part of this research
programme (although she is not herself transgenic). In this case, the
science is so new that judging long-term benefits and risks is difficult.
Some say that animals have rights and should never be subjected to experiments,
regardless of the benefits to humans. They argue that even though chimpanzees,
farm animals and laboratory mice are not members of our species, this does
not give us the right to treat them as we please. Animal rights activists
believe humans are guilty of "speciesism", a notion suggested
in 1975 by the Australian philosopher Peter Singer. Even if we argue that
humans have greater rights, because they are rational and self-conscious,
we have to realise that chimpanzees show intelligence, some self-awareness
and possess a sophisticated social awareness.
Experiment or not - The three "Rs"
ALERT to these ethical problems the British government brought in the Animals
Act in 1986 to control animal experimentation. This incorporates
the "Three Rs" principle developed in 1959 by two researchers
funded by the Universities Federation for Animal Welfare. Rex Burch and
William Russell had travelled Britain interviewing scientists about good
practice in the treatment of experimental animals. The three Rs stand for
reduction, refinement and replacement. Reduction refers
to cutting the number of animal experiments, for example, by harmonising
regulations between different countries so that experiments do not have
to be repeated in each country. Refinement means extracting
the maximum information from the minimum number of experiments. And there
are many possible replacements for animal experiments,
including the use of so-called "lower" organisms—the horse-shoe
crab, for example, tissue slices, cell cultures and computer models (see
Figure 2). In theory, a research scientist cannot use an animal in research
if the information could be obtained by one of these other methods. In
practice, few of the replacements are yet widely accepted as valid alternatives
to animal experiments.
Figure 2
Instead of animals, we could use people in medical trials. Human
clinical trials, carried out before a new drug or surgical treatment
is made generally available, differ from animal tests in two ways.
Firstly, volunteers have to give their fully informed consent. Animals
cannot consent, for obvious reasons. And those recruited on clinical trials
do not usually include children or women of childbearing age (because a
foetus could be exposed to the drug) and prisoners.
Secondly, there should never be any intention to cause harm to the volunteer.
This is not true with animals where most are killed at the end of the experiment,
although there is a legal requirement for pain to be kept to the minimum.
There is a serious ethical issue in human trials, however. To get reliable
information on a new treatment, it is necessary to assign the volunteers
either to a treatment group or a control group that receives only a "dummy" treatment,
or placebo (see Inside Science No. 65, "How a drug is born").
Patients who are seriously ill, however, are understandably anxious to
receive the best treatment. Some doctors feel that depriving half the patients
of treatment is unacceptable; and it is sometimes difficult to recruit
patients to trials, even when the treatment and control groups are swapped
halfway through.
Biotechnology and genetic engineering (see Inside Science No. 105 "Growth
Industry") raise many new ethical issues. Genes are,
of course, the basic material of these technologies, and commercially useful
genes can be found all over the world—in human populations, tropical
plants and even at the bottom of the ocean. But who owns these genes and
who is going to benefit most from their exploitation?
The UN Convention on Biodiversity was agreed at the Rio "Earth Summit" in
1992 seeks to address these concerns. It plans to introduce and enforce
ethical rules. Instead of biological resources such as plants, cells and
genes being regarded as the common property of humanity, they now belong
to their country of origin.
Before this, a drugs company from anywhere in the world could bring plant
and soil samples back from any other country without any questions being
asked. The company could screen its samples for new antibiotics or painkillers,
for example. If it found anything worth exploiting, the rights in that
discovery belonged solely to the company. Now companies must enter into
formal agreements with governments before collecting any samples. Some
of the profits from a successful drug must now be ploughed back into the
country which gave rise to the original source material.
The ethical issue becomes even more sensitive when it comes to dealing
with human genes. The Human Genome Diversity Project is
sampling DNA from populations around the world. Part of the wider Human
Genome Project which was set up in 1990 to identify the 60 000 to 80 000
genes carried by humans, it will study differences between the genetic
make-up of ethnic populations, which, when analysed alongside data for
the prevalence of disease, may point to genetic causes and possible treatments.
However, Native American groups in the US object to their genes being studied
for fear that the information will be used to exploit or discriminate against
them.
Improving nature - Plant genetics
PLANTS which have been genetically modified are already being grown in
open fields, and modified bacteria and viruses are often used to carry
genes into plants and animals. Developers want to boost crop yields for
the world's expanding population by protecting the plants from pests, or
to help the environment by enabling a more efficient use of weedkillers.
But critics point out that making crops resistant to herbicides so that
only weeds get killed when herbicides are sprayed might encourage farmers
to be careless. If the herbicide does not harm their crop, they may stop
worrying about how much they use and perhaps be less careful about where
they apply it.
There is another danger too: genetically modified plants might breed with
wild species and so spread their genes far and wide. Supposing, for example,
a gene for herbicide resistance were to find its way into a weed. The creation
of a superweed that dominated the ecosystem would be an alarming development
and many people would like to wait until we know more about the risks before
proceeding further with plant genetic engineering.
Futuristic babies - Beyond the test tube
AND it's not only plant reproduction that perturbs us. There are now 13
ways to have a baby other than by sexual intercourse. In vitro
fertilisation (IVF) is a well-established technique, producing
so-called test-tube babies. The technique now includes the use of donor
sperm and eggs, and embryo freezing. In future, women may even be able
to have babies by cloning their own body cells. Assisted reproduction has
the obvious benefit of bringing the pleasure and joy of parenthood to childless
women, whether they are infertile single women, lesbians, post-menopausal
women or women wanting a dead partner's child. For some, these new candidates
for parenthood pose ethical problems. For example, one "cost" of
IVF is that children put up for adoption lose out if an infertile couple
opts instead for IVF, while the child of a post-menopausal mother runs
the risk of losing her care and support before reaching adulthood. And
all these techniques are expensive, so how can we be sure that people with
other medical conditions are not being deprived of scarce resources as
a result?
Fertility drugs are an essential part of IVF, but they make the rate of
multiple pregnancy increase from between 1 and 2 per cent to 25 per cent.
It may sound ideal to provide an infertile couple with a ready-made family
in the form of twins, but there are many risks associated with multiple
pregnancy. The mother is more likely to suffer complications such as high
blood pressure, while the babies may be born prematurely, possibly suffering
lifelong health problems as a result. One way around this problem is a
technique called selective reduction: where one or more
of the fetuses is aborted to give the remaining ones a better chance. For
everyone involved, this is a difficult decision to make. The ethical dilemma
here depends upon the status given to a sacrificed fetus: whether or not
it has equal rights with the baby (or babies) that survives.
These ethical issues resemble those faced by other innovative medical procedures.
But IVF and related technologies have created new questions. Firstly, interference
with the processes of reproduction and birth is seen by many people as
being unnatural; some accuse the doctors of "playing God". Then
there are ethical issues about the parental rights and responsibilities
of all those involved in these new reproductive processes (see Figure 3).
When we separate biological and social parenting, it has a radical impact
on our ideas of what makes a family.
Figure 3
IVF may also lead to the creation of "spare" embryos, which are not implanted into the uterus. How should we treat these? Parents can opt to have these frozen for further use, donate them to research or let them perish, but there was an outcry recently when a woman proposed to store an embryo until it suited her to carry it to term.
It is also possible to create embryos in the test tube specifically for
research purposes. As with selective reduction, attitudes towards embryo
research depend upon the status accorded to the embryo. In Britain, an
embryo is seen in the eyes of the law as rather less than a living child
or adult, but still worthy of respectful treatment. Embryo research, which
is permitted up to 14 days after fertilisation, is strictly controlled
by the Human Fertilisation and Embryology Authority.
Of course, there has been a good deal of debate about the ethics of attempting human
cloning. We have to distinguish between cloning of cells for possible
medical uses on a patient and an entire cloned baby. Cloned tissue could
be used for transplants, in which case human cloning would have some potential
benefit—and would cut down on animal experiments. But most people
see the cloning of a new human as unacceptable, mainly on the grounds that
it is an offence against human dignity and that each individual has a right
to his or her own genetic identity.
In fact, there is already a market for clones, but not human ones. People
are already attempting to have their pets cloned. But do animals have a
right to their genetic identity? Should cutting edge research like this
be used to satisfy the need for a pet? On the other hand, might cloned
pets make people happy—as well as contributing to research?
Testing zone - Hard choices
GENETIC advances have helped the treatment of inherited diseases. Single
gene disorders affect about 1 per cent of the population, while many more
common diseases, such as asthma, diabetes, and cancer, have a genetic component.
It is now possible to test high-risk families, or populations, for the
presence of many different defective genes (Figure 5). As the Human Genome
Project nears completion, many more genes involved in disease will be discovered. Gene
tests, therefore, are certain to become more widespread in the
future. There is also the prospect of using gene therapy to insert healthy
genes into ordinary body cells (somatic cells), or even
eggs and sperm (germ-line cells).
Figure 5
There are clear advantages to gene-based medicine. Pre-natal diagnosis of a severe disorder like sickle-cell anaemia allows the family the option of abortion. This saves the whole family the burden of coping with an affected child. It also saves the suffering of the child who would otherwise have been born. Tests given to adults to assess their susceptibility to cancer enables them to have more frequent medical checks. And when tests on a member of an at-risk family prove negative, it does enable them to make plans for the future with confidence.
Genetic testing also brings risks and costs. First, pre-natal testing followed
by termination deprives a child of the chance of life, of some value, however
great the suffering involved. There is also the question of how serious
a disease should be before pre-natal testing is an ethical option. Would
people not want to have children with diabetes, say, if the relevant genes
were discovered, even though people with diabetes can lead a normal life
with treatment? And maybe parents will soon have the option of choosing
embryos without genes which may be found to influence baldness, low intelligence
or even homosexuality? In 1997 a Gallup poll of British parents revealed
that many would opt for genetic enhancement of their children if they could.
If it were proved that genes for aggressive behaviour and homosexuality
existed: 18 per cent would choose an abortion against aggressive behaviour
and 10 per cent against homosexuality, while 5 per cent would like a physically
attractive child. Developments such as these could lead to the development
of a genetic underclass in society, repeating the eugenic horrors of Nazi
Germany.
Fantastic as these ideas may seem, we may see discrimination on genetic
grounds in the near future. Insurance companies could refuse policies to
people carrying faulty genes. There is also concern that employers could
use genetic tests to ensure a super-healthy work force, thereby neglecting
their responsibility to provide a decent working environment.
Genetic tests can also cause psychological suffering in an at-risk family,
particularly where incurable diseases, such as familial Creuzfeldt-Jakob
disease (CJD) or Huntington's disease, are involved. Because these diseases
develop in middle age, the person testing positive may have no symptoms
at the time, but is suddenly facing a death sentence. They may already
have had children, who may be carrying the gene. There is also the issue
of whether to share the information with other family members. This is
why genetic testing is only done in specialist centres, where full information
and counselling are available.
With so many ethical issues raised by modern science, it is easy to understand
why there are now several university departments and legislators who specialise
in ethics. Their work will play an increasing role in helping us to play
our part in deciding between right and wrong in scientific progress.
Figure 4
Ethics is the way to deal with difficult questions of right and
wrong
ETHICS is the study of the moral value of human conduct and of the rules
and principles that govern it. Often known as moral philosophy,
it seeks to distinguish between the good, what is bad, and ways of implementing
these rules. The thorny question of how to define "good" and "bad" lies
at the heart of ethical decision making. The Greek philosopher Plato said
that the most important—and one of the most difficult— question
to answer in real life is "What is the good?" It is hard to define
exactly what we mean by ethics, even experts disagree. Put simply, it refers
to standards of behaviour governed by what is agreed to be acceptable or
correct.
Basic categories of ethical concern fall into two classes: intrinsic and
extrinsic. Intrinsic concerns deal with things that are
thought to be wrong in themselves, such as nuclear weapons and human cloning. Extrinsic
concerns involve the application of developments, neutral
in themselves, but open to misuse or the cause of harm to others. This
classification includes a new drug or an over-powered car.
Many ethical arguments hinge upon the weighing of risks against benefits.
Risk benefit analysis is the basis of an ethical system called utilitarianism,
whose exponents included philosophers Jeremy Bentham (1748-1832) and John
Stuart Mill (1806-1873). In a nutshell, utilitarianism argues that things
are right or wrong in proportion to the amount of pleasure or pain they
produce for communities or individuals.
Another school of ethical thought is based upon natural law.
Here, ethical decisions are made on the basis of how unnatural a scientific
development is. Under Natural Law, genetic engineering is seen as intrinsically
wrong, as is IVF. But the idea that natural is good and unnatural is bad
has weaknesses. Natural disasters, such as earthquakes and volcanoes, cause
immense damage and suffering, and many plants contain potent toxins. You
can also argue that all scientific developments are, to an extent, unnatural.
Natural law also encourages respect for the natural world. And it touches
on the concept of human dignity: people should not be used as a means to
an end, but ascribed value in their own right. This would forbid, say,
the generation of embryos or foetuses to be used for transplants surgery.
It is not just biology and medicine that give rise to ethical problems,
of course. Take, for example, the long debate over nuclear power. Supporters
say it is a clean source of energy which can save the planet from global
warming and provide developing countries with the energy they need to get
ahead. Critics point out the risk of a major nuclear incident has been
underplayed by the industry.
Susan Aldridge is the author of Magic Molecules (Cambridge University Press, 1998).