It is nearly four years ago,
scientists reported that clustered regularly interspaced short palindromic
repeats-Cas9 (CRISPR-Cas9) technology can enable precise and efficient genome
editing in living eukaryotic cells. Since then, scientists are looking for
feasibility of successful somatic and germline editing to eliminate many devastating
genetic diseases. But, it also comes with a thorny international debate as it
opens the door to designer babies and engineered humans.
On August 2, 2017, scientists at the
Oregon Health & Science University reported that they had succeeded for the
first time in United States in correction of the dominant MYBPC3 mutation
that causes a late-onset familial version of hypertrophic cardiomyopathy using
CRISPR/Cas9.
What is DNA editing |
One day after this paper was published
in Nature, the American Society of Human
Genetics (ASHG), and 11 organizations including representatives from the UK
Association of Genetic Nurses and Counsellors, Canadian Association of Genetic
Counsellors, the International Genetic Epidemiological Society, and the US
National Society of Genetic Counselors, as well as the ASHG, published a joint statement in
August concentrating on the prospects for germline alteration.
The statement as published in the AmericanJournal of Human Genetics, again reiterated
that clinical use of germline editing is not allowed at present- these are
genetic changes that would be in every cell of a resulting baby and be passed
on to future generations, viewed as ‘ethical violation’ by many.
On the
plus side, it provides the only hope for some
parents who are carriers of genetic diseases with their best or most acceptable
option for having genetically related children who are born free of these
diseases.
Germline
somatic editing has already entered clinical trials for non-heritable applications,
for treating or preventing diseases or disabilities at this time.
There are three important differences between the two
approaches.
1. Somatic therapies target genes in specific types of cells (lung
cells, skin cells, blood cells, etc), while germline modifications, applied to
embryos, sperm or eggs, alter the genes in all the resultant person’s cells.
2.
Somatic cell modifications are not biologically transferred to
next generations, so it only affects one individual. Germline editing would be inheritable, have
greater impact as it would affect the generations to come.
3. Clinical trials involving somatic cell therapies are around over
two decades now, while human germline editing studies have only just begun this year.
There
are a host of unanswered ethical and scientific
dilemmas, around the procedure but it does not deny the prospects of germline
editing, if the ethical and policy guidelines are met. More stringent
regulations would need to be in place, to ensure safety and efficacy when tinkering
with human nature
Currently, heritable germline editing
is not permissible in the United States. It is only allowed for
purpose of research as the statement published in the American Journal
of Human Genetics after 16 months of deliberation, “Currently, there
is no reason to prohibit in vitro germline genome editing on
human embryos and gametes, with appropriate oversight and consent from donors,
to facilitate research on the possible future clinical applications of gene
editing.”
It suggested that research into
genetic modifications should continue as long as it doesn’t lead to a
pregnancy.
This ASHG statement is the second set
of recommendations issued in 2017, following an exhaustive 300 pages NationalAcademy of Sciences, Engineering, and Medicine (NASEM) document “Human Genome
Editing: Science, Ethics, and Governance.”
The NASEM statement is more wide and
covers somatic gene editing, but both the statements expressed reservations currently
on using germline editing for creating ‘engineered humans’, but did not deny
the possibility of it in future.
Both statements also called for public
funding, for manipulating human embryos and fetuses for research, arguing that
without funds the research may move offshore, where less stringent regulations
and transparency prevails and that may result in rogue experimentation.
Human genome editing is already widely
used in basic research and is in the early stages of development and trials for
clinical applications that involve non-heritable (somatic) cells.
The Chinese and U.K laws are already in place.
The Chinese and U.K laws are already in place.
Biologist Paul Knoepfler estimates
that genetically modified people will no longer be a science fiction fantasy;
it's a likely future scenario. Within fifteen years, scientists could use the
gene editing technology CRISPR to make certain "upgrades" to human
embryos — from altering physical appearances to eliminating the risk of
auto-immune diseases.
As Victor Hugo said, “there is nothing
more powerful than an idea whose time has come.” So, now it’s a question of “when”,
instead of “never”.
Here is a video by Françoise Baylis,
a philosopher and professor at Dalhousie University, is one of the foremost
voices among bioethics scholars worldwide.
Her mission is to foster an inclusive
dialogue on what should and should not be allowed through gene editing. As the
consequences of these decisions will affect future generations
Francoise Baylis – Breaking the Wall Between Gene Science and Ethics @Falling Walls Conference 2016 from Falling Walls on Vimeo.
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