This article was originally prepared for the online magazine TNTY
Futures. Written by Daniel Drell (U.S. Department of Energy) and Anne
Adamson (Oak Ridge National Laboratory), it speculates about how genetic
advances sparked by the Human Genome Project may affect the practice of
medicine in the next 20 years.
The first phase of the ambitious international effort to determine the entire sequence of the
human chromosome set is virtually complete. Human Genome Project scientists plan to
finish the human sequence by 2003, along with a database of the most common sequence
variations that distinguish one person from another. This knowledge base, freely available
to any interested person over the Internet, will revolutionize biology and medicine. But
how? What will be different 20 years from now because the human genome was
Only time will prove the accuracy of the following predictions, but here is a list of some
effects we might expect in 2020.
More Effective Pharmaceuticals
A virtually complete list of human gene products will give us a vast repertoire of potential
new drugs. From 500 or so drugs in 2000, at least six times this number will have been
identified, tested, and commercialized in 2020. All will be manufactured by recombinant
DNA technology so they will be "reagent-grade pure," just as human insulin and growth
hormone are today.
Your medical record will include your complete genome as well as a catalogue of single
base-pair variations that can be used to accurately predict your responses to certain drugs
and environmental substances. This will permit you to be treated as a biochemical and
genetic individual, thus making medical interventions more specific, precise, and
successful. In addition, the increased power of medicine to predict susceptibility to specific
diseases will allow you to alter your lifestyle to reduce the likelihood of developing such
diseases or to be treated with preventive or disease-delaying medicine.
Treatment failures occasionally happen today with drugs for hepatitis C infections,
antihypertensives, and certain anti-depressants (selective serotonin reuptake inhibitors like
Prozac). In the next 15 to 20 years, more effective drugs will be developed, and doctors
will test individual genetic profiles against panels of drugs available for a specific condition
and choose the treatment with the greatest potential benefit.
Today, some 100,000 people die each year from adverse reactions to drugs, and millions
of others must bear uncomfortable or even dangerous side effects. We see such current
examples as heart-valve abnormalities from diet drugs, muscle damage from some
hormone-regulating drugs, and nervous system effects with certain types of anti-depressant medications. As genes and other DNA sequences that influence drug response
are identified, we can expect the number of toxic responses to drop dramatically and most
side effects to be eliminated.
Another consequence of greater knowledge about individual variation is more disturbing,
and we may face some unpleasant consequences unless society makes some hard choices.
These considerations include the likelihood that your medical information will be available
to others not in the medical profession--your insurer or employer, perhaps. Employers
may have a strong motive to learn about your risks of developing certain conditions and to
avoid hiring you or restrict the kinds of work you may do.
Genetic Testing, Therapy
Although now plagued by technical difficulties, gene therapy for single-gene diseases will
be routine and successful in 20 years. Certain aberrant disease-associated genes will be
replaced with normally functioning versions, and several hundred diseases will be curable.
Neonatal genetic testing for these treatable conditions will be routine.
Some of the mysteries of early embryonic development will be solved. We should know
the timing of expression of most, perhaps all, of the human gene set. We may have learned
how to direct differentiation so that a desired cell type or even relatively "simple" organs
and parts of more complex organs can be grown for transplantation. In 2020, we will have
made substantial progress towards true "cloning" of certain organs, but many difficult
technical steps will remain before successful cloning of a heart or liver.
As genetic testing using DNA sequence becomes more common, less expensive, and more
accurate, it will be used commonly and reliably in cases of mistaken identity, false or
misattributed paternity, and the identification of missing persons. Misguided attempts to
ascribe behavioral tendencies to a person's genes will cause many problems, not least for
the courts that must resolve disputes when an individual's behavior and actions conflict
with laws. Should society (via the courts) interpret behavior as a consequence of free will
or as influenced by genetic constitution? At what point does society mitigate responsibility
On the brighter side, an inevitable consequence of the genome project will be a much
greater understanding of fundamental biology. Already, some three dozen organisms
(mostly one-celled microbes) have been completely sequenced. The fruit fly, the latest
organism to be sequenced, is being used to model the essential features of human
disorders such as Parkinson's, making possible a powerful genetic approach to garnering
knowledge about diseases as well as to developing more effective treatments. In 2020,
perhaps 1000 complete genomes will be in hand. Besides furnishing insights into
evolution, this vast repertoire of new genes and their products can be explored for their
potential in solving challenging problems such as environmental cleanup.
We will fitfully and slowly gain some insights into biological complexity. In 2020, we will
know how to build a functioning cell capable of free-living existence. We will understand
certain pathways used by this simplest cell, but there still will be unanswered questions
about it. We will be virtually no closer than we are today to the mysteries of such true
"emergent" properties as intelligence in complex multicellular organisms.
So the Human Genome Project will have vast and largely positive impacts on people living
in 2020. Of the various predictions noted above, the last two are the most profound
because the most powerful and momentous impacts come from fundamental knowledge,
usually in unforeseen ways. As this astonishing treasure trove is introduced into society,
we need to be alert to challenges and misuses of the knowledge about ourselves. Society
as a whole, not just genome scientists, must address these considerations. It has to be all
of us. [Daniel Drell (DOE) and Anne Adamson (HGMIS)]