| CNN | - |
London
(CNN) -- The United Kingdom took a step Friday toward being the first
country in the world to allow a pioneering in vitro fertilization
technique using DNA from three people that could prevent mitochondrial
diseases but that also raises significant ...
UK takes step toward 'three-parent babies'
updated 10:46 AM EDT, Fri June 28, 2013
A pioneering in vitro fertilization technique utilizes DNA from three people, effectively creating a "three-parent baby."
STORY HIGHLIGHTS
- NEW: "Little is known about the short- and long-term genetic effects," says a U.S. bioethicist
- Government takes a step toward allowing an IVF technique involving DNA from 3 people
- It is intended to prevent mitochondrial disorders being passed on from mother to child
- Mitochondria are "powerhouse" cells of the body; defects can cause serious health issues
One in 6,500 babies in
the United Kingdom is born with mitochondrial disorder, which can lead
to serious health issues such as heart and liver disease, respiratory
problems and muscular dystrophy.
Problems with
mitochondria, the "powerhouse" cells of the body, are inherited from the
mother, so the proposed IVF treatment would mean an affected woman
could have a baby without passing on mitochondrial disease.
But the cutting-edge IVF
technique, which involves transferring nuclear genetic material from a
mother's egg or embryo into a donor egg or embryo that's had its nuclear
DNA removed, raises ethical questions.
2012: Breaking down fertility options
The new embryo will
contain nuclear DNA from the intended father and mother, as well as
healthy mitochondrial DNA from the donor embryo -- effectively creating a
"three-parent" baby.
The amount of donor DNA
in the mitochondria will, however, be much less than the parental DNA in
the nucleus, which determines the baby's characteristics.
The UK government plans
to consult on draft regulations on the fertility treatment later this
year, with the intention of putting the measure before parliament next
year. At the moment, only unaltered eggs and embryos can be used for in
vitro fertilization.
"Mitochondrial disease,
including heart disease, liver disease, loss of muscle coordination and
other serious conditions like muscular dystrophy, can have a devastating
impact on the people who inherit it," said the UK's chief medical
officer, professor Dame Sally Davies.
Since scientists have
developed "ground-breaking new procedures" that could prevent these
diseases being passed on, Davies said, "it's only right that we look to
introduce this life-saving treatment as soon as we can."
The government says public consultation shows there is "overall support" for the treatment.
But Dr. David King,
director of Human Genetic Alert, a London-based watchdog group, opposed
use of the technique Friday -- saying it opened the door to the creation
of "designer babies" -- and disputed the results of the public
consultation, saying not enough weight has been given to online polling.
"These techniques are
unnecessary and unsafe and were in fact rejected by the majority of
consultation responses," he said in a statement.
"It is a disaster that
the decision to cross the line that will eventually lead to a eugenic
designer baby market should be taken on the basis of an utterly biased
and inadequate consultation."
King told CNN that
conventional egg donation already allows a mother to bear a child
without passing on a mitochondrial disorder, so the benefit of the new
technique would only be to allow the baby to be genetically related to
her.
"While I can understand
that, that's not a medical benefit to anybody -- and you have to weigh
it against the risks of invasive techniques that will clearly carry a
risk to the child," he said.
There's also a "risk to
society at large," he said, because once the ethical line over
modification of human DNA has been crossed, the door will be opened to
"the next step and the next step after that."
"That's why governments
around the world over the last 20 years have said 'we won't allow you to
genetically engineer human beings,' " he said.
Even if approved by
lawmakers, more research is needed to ensure that the procedure actually
works in humans and can be carried out safely, King said.
The government's
announcement Friday prompted a slew of UK media headlines -- and will
probably continue to divide the scientific community.
The UK-based Nuffield
Council on Bioethics, which carried out a six-month inquiry into the
ethical issues around the technique, concluded that the health and
social benefits of living free from mitochondrial disorders meant that
"on balance ... if these novel techniques are adequately proven to be
acceptably safe and effective as treatments, it would be ethical for
families to use them."
Its working group also
concluded that "mitochondrial donation does not indicate, either
biologically or legally, any notion of the child having either a 'third
parent,' or 'second mother.' "
But University of Notre
Dame law professor O. Carter Snead, a bioethicist who specializes in the
governance of science, medicine and biotechnology, urged the United
Kingdom to "proceed slowly and cautiously" given the "unresolved safety
and ethical questions" around the new technique.
"Little is known about
the short- and long-term genetic effects of this procedure on children
born with its aid," he said. "It would be an ironic tragedy if this
procedure were rushed from bench to bedside, only to harm the very
children it was meant to help.
"Moreover, there remain serious questions about the ethics of conceiving children with three genetic progenitors or 'parents.' "
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