Human Transgenesis - Definitions  Technical Possibilities and Moral Challenges
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Human Transgenesis - Definitions Technical Possibilities and Moral Challenges

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developments of the retroviral gene delivery
systems. This temporary moratorium ended when a unique group of retroviruses,
the lentiviruses, started to be evaluated as safer and more efficient vectors than the
other retroviral vectors being employed. Lentiviruses have the capacity to efficiently
transduce non-dividing cells, including hematopoietic stem cells and cells from the
central nervous system, liver, eye, heart and pancreas (Wiznerowicz and Trono 2005).
Moreover, specific genetic modifications of lentiviral vectors have rendered them
able to mediate long-term transgene expression in vivo, whereas the unwanted
insertion of the lentivirus genome into the host DNA has been considerably diminished,
although not completely abolished (Cockrell and Kafri 2007). Successful pre-clinical
studies using these new vectors to treat genetic disorders rapidly appeared and
provided excellent outcomes in animal model studies of Alzheimer's, Parkinson's
and Huntington's diseases (Wong et al. 2006; Wakeman et al. 2011); immunodefi-
ciencies and various haemoglobin disorders (Levasseur et al. 2003; Mostoslavsky et
al. 2006).
Technical innovations in transgenesis were also accompanied by regulatory improve-
ments, which were developed by special committees formed to evaluate and control the
human clinical trials involved in gene therapy and gene delivery methods. An example
of such a regulatory body is the Center for Biologics Evaluation and Research, a branch
of the US FDA that has set guidelines for the long-term follow-up of patients enrolled in
human gene transfer studies (Nyberg et al. 2004). With all favourable conditions now
in place, the therapeutic applications of lentiviral vectors are beginning to transition
from pre-clinical animal models to corrective therapy in humans. Importantly, the
comeback of the gene transfer approach to treat human genetic disorders after the
iconic failures of a decade ago have prompted research with other viral vectors,
including adeno-associated viral vectors, which have been used to treat heart con-
ditions in a number of current human clinical trials (Kawase 2011).
Thus, therapeutic gene transfer techniques that employ viral vectors and other
emerging methods are not simply a technological promise; they are an actual reality.
Human gene transfer can be used to potentially treat many, if not most, incurable,
infectious and genetic maladies. Going even further, different genetic traits can also
be introduced into the human genome with objectives that are not only therapeutic but
also geared towards the enhancement of normal human capacities. It would not be
much of an exaggeration to say that limitations for the use of gene transfer in humans
are becoming less technical and more ethical in nature.
3 Morals and the Pursuit of Transgenic Enhancements in Human Beings
3.1 \u201cHuman Nature\u201d is Transgenic
In the Western World, humans have sought to establish themselves as a separate class
of beings in the physical and natural world, distinguished from other beings by an
array of unique and, more often than not, God-given attributes that make them special
and superior to other life forms (cf. Mirandola 1994). \u201cHuman nature\u201d is a key
concept through which this idea has been communicated. This idea is deeply rooted
F.G. da Fonseca et al.
in the theological doctrine of Christianity, which in the middle ages defined man as an
\u201cindividual substance of rational nature\u201d2 sharing some of God's divinity by being
created in His image\u2014a by-product of perfection in the form of a complete and
immutable essence.
However, the aforementioned developments in the fields of genetic engineering
and molecular biology have helped to demolish the view that human nature is a static
entity or that the DNA could be likened to an \u201cessence\u201d of life. Humans are highly
transgenic. Transgenesis is not simply an accidental factor in the development of the
human species but a fundamental force that drives biological evolution, including that
of humans. This conclusion should be enough to brush aside arguments claiming that
the use of gene therapy for purposes of treatment/enhancement could alter or modify
human nature. Since transgenic interventions in the genome would not be qualita-
tively different than naturally occurring events, such interventions would not alter
human nature more than natural transgenesis already does.
If transgenesis occurs as a non-intentional process that drives biological novelty
and adaptation, why not use it for human purposes? Some could still argue that while
intentional transgenesis could be attempted for the purposes of restoring normal
encoding DNA in diseased genomes, artificially pushing for biological innovation
could be extremely dangerous because it represents a step beyond natural design into
a realm of biology and biological risk that is largely unknown.
However, the supposed gap between these two types of interventions is illusory.
Notably, the technical means for achieving both goals are largely the same, and thus,
so are the risks. The leap into the unknown is not that much of risk either because
scientists are likely to work on gene sequences that are extensively and exhaustively
researched for their properties and effects as much as they are for treatment and
enhancement. This concern could be addressed more directly by saying that any gene
therapy intervention in humans should follow strict risk assessment protocols, and no
clinical trial should be conducted without sufficient evidence that the intervention
might prove to be beneficial and that the risks are acceptable for scientists, the
subjects and society.
Nature is not an intentional entity. As such, nature is not wise or beneficent in
controlling transgenesis.3 Transgenesis has occurred as a matter of chance in organ-
isms that are prone to its occurrence, and has been incorporated as a populational
genomic feature in situations in which transgenic alterations increased the propensity
of organisms to survive and reproduce in their environments. On the other hand, there
are good reasons to learn how and why non-intentional transgenesis has helped
organisms survive, and what sort of phenotypical traits have successfully emerged
from it. Pursuing this knowledge should be an imperative.
3.2 Making Transgenic Persons
The risks associated with genetic engineering are many: accidental infections with
viral vectors, the development of cancerous cell growths and the creation of docile, or
3 In fact, nature\u2019s wisdom at large is a debatable proposition or ethical claim (cf. Bostrom and Sandberg
2009; Powell and Buchanan 2011).
2 [N]aturae rationabilis individua substantia (Boecio 2005: 168).
Human Transgenesis: Technical Possibilities and Moral Challenges
less autonomous sentient beings, etc. Such concerns would seem to warrant against
transgenic interventions in human embryos. However, it should be pointed out that
designing human beings is not a new thing, and that the risks presented by genetic
engineering are not higher or more daunting than the risks involved in other existing
forms of manipulating human persons (i.e., educational processes, nootropic nutri-
tion, pharmaceutical interventions, surgical interventions, stimulus control, cognitive
therapy, etc.).
As Sagoff (2005: 72) reported, there is no reason to believe in \u201cgenetic exception-
alism,\u201d the idea that genes serve a larger or more essential role in determining one's
physical appearance or personality than other environmental factors. The genome has
a (limited) scope of influence and is only one among many factors. In this sense,
genetic engineering techniques are an effective way to manipulate the \u201cgene factor\u201d
as merely another addition to the large array of manipulation tools that we already
possess. Thus, because what can be changed by means of genetic engineering is not at
all different from what can be altered by other tools, transgenic interventions present
only a quantitative change to the existing framework for changing human