Mapping the human genome
Medical science and
technology have made great strides in recent times. The ethical values amidst
the various achievements have to be evaluated as science tends to progress in
isolation. In a recent conference of the WHO, in Tokyo, in which I was also
privileged to participate representing India, some important decisions were
made. Most of the nations were represented and included leading medical
scientists and researchers. A declaration on medical ethics which is now known
as the ‘Tokyo Declaration’ has come out as a product of this conference.
Discussion of human genetics is dominated today by the efforts now under way
on an international basis to map and sequence the human genome. Such attention
is warranted by the scale of the undertaking and its expected contribution to
knowledge about human biology and disease. At the same time the nature of the
undertaking concerned as it is with the basic elements of life, and the
potential for abuse of the new knowledge which the project will generate, are
giving rise to anxiety. The conference agrees that efforts to map the human
genome present no inherent ethical problems but are eminently worthwhile,
especially as the knowledge revealed will be universally applicable to benefit
human health. In terms of ethics and human values, what must be assured are that
the manner in which gene mapping efforts are implemented adheres to ethical
standards of research and that the knowledge gained will be used appropriately,
including in genetic screening and gene therapy.
Do technical advances dehumanise the patient?
Public concern about the growth of genetic knowledge stems in part from the
misconception that while the knowledge reveals an essential aspect of humanness
it also diminishes human beings by reducing them to mere base pairs of
deoxyribonucleic acid (DNA). This misconqption can be corrected by education of
the public and open discussion, which should reassure the public that plans for
the medical use of genetic findings and techniques will be made openly and
responsibly.
Some types of genetic testing or treatment not yet in prospect could raise
novel issues, for example, whether limits should be placed on DNA alternations
in human germ cells because such changes would affect future generations, whose
consent cannot be obtained and whose best interests would be difficult to
calculate. The conference concluded, however, that for the most part present
genetic research and services do not raise unique or even novel issues, although
their connection to private matters such as reproduction and personal health and
life prospects, and the rapidity of advances in genetic knowledge and
technology, accentuate the need for ethical sensitivity in policy making.
Disclosure without consent
It is primarily in
regard to genetic testing that the human genome project gives rise to concern
about ethics and human values. The identification, cloning, and sequencing of
new genes without first needing to know their protein products greatly expand
the possible scope for screening and diagnostic tests. The central objective of
genetic screening and diagnosis should always be to safeguard the welfare of the
person tested: test results must always be protected against disclosure without
consent. Confidentiality must be ensured at all costs, and adequate counselling
must be provided. Physicians and others who counsel should endeavour to ensure
that all those concerned understand the difference between being the carrier of
a defective gene and having the corresponding genetic disease. In autosomal
recessive conditions, the health of carriers (heterozygotes) is usually not
affected by their having a single copy of the disease gene; in dominant
disorders, what is of concern is the manifestation of the disease, not the mere
presence of the defective gene, especially when years may elapse between the
results of a genetic test and the manifestation of the disease.
Clinical application
The genome project will
produce knowledge of relevance to human gene therapy, which will very soon be
clinically applicable to a few rare but very burdensome recessive disorders.
Alternations in somatic cells, which will affect only the DNA of the treated
individual, should be evaluated like other innovative therapies. Particular
attention by independent ethical review committees is necessary, especially when
gene therapy involves children, as it will for many of the disorders in
question. Interventions should be limited to conditions that cause significant
disability.
The modification of human germ cells for therapeutic or preventive purposes
would be technically much more difficult than that of somatic cells and is not
at present in prospect. Such therapy might, however, be the only means of
treating certain conditions, so continued discussion of both its technical and
its ethical aspects is therefore essential. Before germ- line therapy is
undertaken, its safety must be very well established, for changes in germ cells
would affect the descendants of patients.
Responsibility of researchers
Genetics
researchers and therapists have a strong responsibility to ensure that the
techniques they develop are used ethically. By insisting on truly voluntary
programmes designed to benefit directly those involvedm they can ensure that no
precedents are set for eugenic programmes or other misuse of the techniques by
the state or the private parties. One means of ensuring the setting and
observance of ethical standards is continuous multidisciplinary and trans-
culture dialogue.
The need of developing countries should receive special attention to ensure
that they receive their due share of the benefits that ensure from the human
genome project. In particular, methods and techniques of testing and therapy
that are affordable and easily accessible to the populations of such countries
should be developed and disseminated whenever possible.
A. K. Tharien, Christian
Fellowship Hospital, Oddanchatram, Tamil Nadu 624 619.