Biomedical Engineering Reference
In-Depth Information
be a type of engineering. However, few engineers actually
perform human genetic engineering. In fact, most of it is
accomplished by biologists. And, these are mainly phy-
sicians (e.g., those in IVF clinics) and biomedical re-
searchers (e.g., those conducting DNA work under the
auspices of biochemistry). So, the lay public and clergy
work in passive genetic engineering (e.g., choosing
spouses) and biologists work in active genetic engineering
(e.g., cellular biochemists). Where does that leave the
engineering profession?
Arguably, engineers' work is affected by that of other
professions. Thus, we need at least some preparation for
the bioethical issues that are certain to arrive in our in-
dividual specialties.
The emergence of genetic manipulation has been
rapid. Scientists made huge gains throughout the 1900s
in discovering DNA and its structure. In 1977, Genetech
became the first company to use recombinant DNA
technology. This served as a catalyst in the industry by
being the first of many opportunities and discoveries
throughout the 1980s and 1990s. In 1988, the Human
Genome Project started with the goal of determining the
entire sequence of DNA in humans. Since then, genetic
engineering has been the focus of a myriad of ethical
questions and debates.
Teachable Moment: Nanog
In Celtic legend, Nanog (short hand for
Tir Nan Og
) was
a land of the eternally young. Fittingly, the Nanog
molecule is at the threshold of what could be the
unraveling of the need for embryonic stem cells to
advance medical science. Scientists have argued that
embryonic stem cells are unique in their ability to develop
into any type of cell in the body, and further that they
show great, yet still unfilled, potential to replace and to
mend damaged tissue. Thus, the argument goes,
embryonic stem cells are essential for such medical
treatments.
Recently, researchers have become aware that the
Nanog may someday allow ordinary cells to make use of
that wonderful attribute.
Quite recently, working from the premise that amniotic
fluid is known to contain multiple cell types derived from
the developing fetus, researchers at Wake Forest
University have advanced that state of science to show
that these cells are able to produce an array of
differentiated cells, including those of adipose, muscle,
bone, and neuronal lineages.
13
The amniotic fluid-derived
stem (AFS) cells are different from both adult and
embryonic stem cells but share qualities of both.
According to the lead researcher, Anthony Atala, AFS
cells, like human embryonic stem cells, can double every
one and a half days and can extensively differentiate.
However, like adult cells, they do not seem to form
tumors when implanted. As a scientific and potentially
ethical bonus, AFS cells are readily gathered from
amniotic fluid or placenta, making way for a potentially
vast supply of cells available for therapeutic purposes.
Questions
1. What are some of the scientific obstacles that need
to be overcome in Nanog research?
2. If the science supports this advance, what may be
some of the reasons that scientists and others may
still be skeptical of these findings?
3. Compare this type of skepticism to Kuhn's
descriptions of the scientific community during
a paradigm shift.
Patenting life
Bioprospecting, the search for natural substances of
medicinal value, is a very divisive topic in bioethical de-
bates. In November 1999, the US Patent and Trademark
Office rescinded a patent on the plant species
Banister-
iopsis caapi
held by a Californian since 1986. The plant is
sacred to tribal communities living in the Amazon Basin
and is the source of the hallucinogen
ayahuasca,
used in
their religious rituals. In addition to being a harbinger of
the complications of religious and cultural respect, it
presages the looming, bitter debates about the extent to
which biological materials can be ''owned.''
In fact, in one form or the other, humankind has been in
the bioprospecting business for millennia. Like many
bioethical issues, emerging technologies and research have
changed the landscape (literally and figuratively) dramat-
ically. And, powerful interests, such as pharmaceutical
companies, see natural materials (including certain genes)
as lucrative ventures that need to be harnessed for profit.
For example, the biotechnology firm, Diversa Inc., en-
tered into an agreement with the National Park Service to
find efficacious and beneficial microbes in the geysers and
springs in Yellowstone National Park. However, this met
with much resistance and ultimately the agreement was
suspended by a federal court ruling.
As controversial as patents on plant genetic material
are, they pale in comparison to the bioethical debates
most basic level, genetic engineering is artificially modify-
ing the genetic code of an organism. But what is artificial?
Obviously, an active approach like inserting DNA into
a cell is artificial, but what about passive techniques like
choosing potential mates with certain traits as the spouse
and the future parent of one's children?
Since engineering is the application of sciences to
address societal needs, then genetic engineering seems to
