h/t CNA
By
Adelaide Mena
Washington
D.C., Feb 23, 2017 / 02:50 am (CNA/EWTN News).- Recent
American guidelines for human gene modification have raised important ethical
questions, especially with regard to modifying the genes of unborn children and
of reproductive cells.
The
National Academy of Sciences last week released a 261-page report on guidelines for
editing the human genome to treat diseases and other applications. The report
covers a wide array of topics, from the editing of adult cells for therapies
such as cancer treatment, to the editing of embryos and germ cells
(reproductive cells, i.e. ova and sperm), to the question of human enhancement.
John
DiCamillo, an ethicist at the National Catholic Bioethics Center, spoke to CNA
about the perils and the promises of gene editing, as well as the oversights
contained in the National Academy of Sciences' report.
“Gene
editing generally can be morally legitimate if it has a directly therapeutic
purpose for a particular patient in question, and if we’re sure we’re going to
limit whatever changes to this person,” DiCamillo explained. In this regard,
the report’s guidelines for laboratory treatment of somatic – or
non-reproductive – cells and human trials of somatic cell treatments were
reasonable, he noted.
DiCamillo
pointed to upcoming clinical gene therapy trials for cancer and proposed gene
therapy treatments for disorders such as sickle cell disease. However, it’s
important to limit these trials to non-embryonic persons, to ensure that the
modifications – intended as well as unintended – are not carried in the
patient’s reproductive cells.
While
this would mean that patients treated for inheritable diseases “could still
transmit it to their children,” any children who then developed the disease
could themselves be treated through the same process.
The
question of transmission to descendants opens two more points discussed in the
National Academy of Sciences report: the modification of ova and sperm, as well
as edits to the genomes of embryos. Both changes would mean that people would
maintain these edits in all of their cells for all of their lives – and could
pass on these edited genes to new generations.
“There
could be limited situations that could exist where the germ line could be
legitimately edited. In other words, making changes to sperm, to eggs, or to
early embryos as a way of potentially addressing diseases – inheritable
diseases and so forth,” DiCamillo stated.
However,
permitting edits to germ line cells could also be “very dangerous on multiple
levels,” he warned.
There are
considerable, and not yet fully controllable, risks to genetic manipulation. A
person conceived with edited genes could experience a range of “unintended,
perhaps harmful, side effects that can now be transmitted, inherited by other
individuals down the line.” An embryo who experiences gene modification could
also carry and pass on edited genes, particularly if edits were performed
before his or her reproductive cells began to differentiate themselves.
The
National Academy of Sciences' regulations surrounding germ cells and embryos
are also problematic for what they overlook, DiCamillo commented.
Manipulating
sperm and ova requires removing them from a person’s body; if conception is
achieved with these cells, it is nearly always through in vitro methods. This
practice of in vitro fertilization is held by the Church to be ethically
unacceptable because it dissociates procreation from the integrally personal
context of the conjugal act.
In
addition, scientific researchers rarely differentiate between experimentation
on sperm or ova – which are cells that come from a human subject – and embryos,
which are distinct persons with their own distinct genomes, DiCamillo noted.
The
National Academy of Sciences’ guidelines reflect this lack of distinction
between cells and embryos. “That’s very misleading because embryos are not germ
line cells; they are new human beings,” DiCamillo said.
For
research on embryos to be ethical, he continued, therapies should be ordered to
treating and benefitting that “that particular embryo, not just for garnering
scientific knowledge or seeing what’s going to happen.” DiCamillo condemned
policies that see destruction of embryonic persons as a back-up if research
does not go as planned, as well as current policies that require destruction of
embryos as standard procedure.
“We’d be
in that area of very dangerous exploitation of human life and destruction of
human life,” he warned.
While the
guidelines stumble across ethical roadblocks in regards to gamete and embryo
research, the new report’s rules regarding human enhancement are strong,
DiCamillo said.
The
ability to edit genomes could also be used for purposes other than medical
treatment. A whole host of human traits could be enhanced or changed, such as
vision, intelligence, or abilities. “There’s any number of things that we could
do to change the qualities of human beings themselves and make them, in a
sense, super-humans … this is something that would also be an ethical problem
on the horizon,” he warned.
The existence
of these gene altering therapies raises a question of how much modification and
enhancement is permissible. DiCamillo praised the report for its recommendation
“entirely against enhancement efforts and that these should not be allowed.”
Currently,
gene editing of both germ cells and somatic cells is legal in the United
States, including on embryos. However, various US government institutions have
policies in place prohibiting federal funding of such research efforts on germ
cells and on embryos.
Furthermore,
Food and Drug Administration regulations prohibit gene modification on viable
human embryos – meaning that human embryos who receive gene modification are
always destroyed.
The new
guidelines from the National Academy of Sciences are significant because they
lay a groundwork for future policy on human gene modification. They cautiously
welcome the use of gene therapy on human embryos who are not later targeted for
destruction after experimentation concludes.
DiCamillo
recalled, however, that “they are merely guidelines – they are advice from the
National Academy of the Sciences to the government in regards to future policy.
This is not itself a new regulation or policy that the government has
established.”
The
ethics of gene editing has been questioned for several years – the Congregation
for the Doctrine of the Faith addressed the issue in Dignitas
personae, its 2008 instruction on certain bioethical questions.
It has become more pressing recently, however, because a new technique known as CRISPR is easier to use and less
expensive than previous means of gene editing.
Although
the ethical questions surrounding gene modification are many and there are a
number of problematic applications of these technologies, DiCamillo cautioned
Catholics not to renounce completely human gene modification: “We don’t
want to be hyper-reactive to the dangers. We have to realize there’s a great
deal of good that can be done here.”
He
pointed again to the kinds of modifications that can treat deadly genetic
diseases and treatments that can be done in an ethical manner, with full
respect to the dignity of human persons.
“We do
need to be attentive to where the dangers are,” he warned, “but we don’t want
to … automatically consider any kind of gene editing to be automatically a
problem.”
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