IVF techniques that, if approved by Parliament, would for the
first time permit the transfer of genetically modified embryos into
the womb are the subject of a new consultation by the Human
Fertilisation and Embryology Authority (HFEA).
The techniques have been developed to enable women who suffer
from a form of mitochondrial disease, caused by faults in the DNA
of mitochondria (often described as the human cell's batteries),
from passing it on to their children.
IVF is used to fertilise a mother's egg, containing "unhealthy"
mitochondria, with the father's sperm. The nucleus of the
fertilised egg is then collected and transplanted into a donor egg
containing healthy mitochondria, but with its own nucleus
More than 99 per cent of the child's genes would come from the
mother and father, while less than one per cent would be inherited
from the donor. This change would affect the germ line, meaning
that the donor's mitochondrial DNA would be passed on to future
generations. Germ-line modifications have never been permitted on
A change in the law is required for clinical trials to begin.
The Government has asked the HFEA to "take the public
The website for the consultation (which is open until 7
December) outlines issues that the proposals raise, including
concerns that they could constitute "the first step on a slippery
slope to genetic modification, perhaps for trivial purposes", and
questions about the impact of inheriting DNA from three people on a
child's sense of identity, and society's concepts of parenthood. It
also notes that, even if the techniques were legalised, they would
remain experimental, and the impact would not be fully known until
after the children were born.
An ethical review published by the Nuffield Council on Bioethics
in June concluded that, if the techniques were "adequately proven
to be acceptably safe and effective", it would be "ethical" for
families to use them, owing to "the health and social benefits" of
freedom from mitochondrial disorders, and where potential parents
prefer to have genetically related children.
The review discusses the significance of the proposal to
legalise an alteration to the germ line. The UN's Universal
Declaration on Human Genome and Human Rights describes the human
genome as "the heritage of humanity", and gives the International
Bioethics Committee a duty to identify "practices that could be
contrary to human dignity, such as germ-line interventions".
The director of Human Genetics Alert, Dr David King, said that
the techniques "set a precedent for allowing the creation of
genetically modified babies", and he questioned their safety.
"Bioethicists and governments have long insisted that modification
of the human germ line be banned, because it could allow a new and
extremely dangerous form of eugenics."
The Christian Medical Fellowship called the techniques
"unnecessary, unethical, and overhyped". It argues that
alternatives such as adoption and egg donation are already
The director of research at the Muscular Dystrophy Campaign, a
charity that funds research into the techniques, Dr Marita
Pohlschmidt, said: "For women who have been dealt the heavy blow of
living with mitochondrial disease, the prospect of bearing healthy
children is of immeasurable value. . . It is only through
communicating the reality of this complex procedure - and the
issues and questions it presents - that reservations can be
The HFEA states that about one child in 200 is born each year
with a form of mitochondrial disease. But the Nuffield report notes
that most cases are mild or asymptomatic. About one in 6500 is
estimated to develop a more serious, even fatal, mitochondrial