manipulation of embryonic nuclear DNA/mitochondrial DNA

[Guest guest]

no matter one's beliefs, there is good research currently ongoing to

help!

http://news.bbc.co.uk/1/hi/health/4228712.stm

Concern over three-parent embryo

The aim is to get healthy offspring free of inherited genetic

disorders

Critics have expressed horror about research to create a human

embryo with genetic material from three parents.

The Human Fertilisation and Embryology has reversed its ban on the

controversial proposal from the University of Newcastle.

The researchers will transfer genetic material created when an egg

and sperm fuse into another woman's egg.

The groundbreaking work aims to prevent mothers from passing certain

genetic diseases on to their unborn babies.

Such diseases arise from DNA found outside the nucleus, and thus

inherited separately from DNA in the nucleus.

They are collectively called mitochondrial diseases.

Mitochondria are small complex structures, which exist in every cell

of the body, except red blood cells. They are responsible for

producing the energy that we need to grow and live.

The innovative approach being tested may lead to a treatment for

mitochondrial myopathies

Dr on of the Muscular Dystrophy Campaign

Q&A: Two mother embryo

One unique feature of mitochondria is that they have their own DNA -

mitochondrial DNA, which is inherited from the mother only.

If this DNA is faulty, a mitochondrial diseases occurs. At present,

no treatment for mitochondrial diseases exists.

Studies in mice show it is possible to prevent the transmission of

mitochondrial disease by moving the pronuclei - the genetic material

which will go on to form a nucleus - from a fertilised egg

containing bad mitochondria and putting it into another fertilised

egg which only contains good mitochondria.

Professor Doug Turnbull, professor of neurology at Newcastle

University, and Dr Herbert, scientific director of Newcastle

Fertility Centre at the city's Centre for Life, now plan to do the

same in humans.

US scientists at the Institute for Reproductive Medicine and Science

of St Barnabas, New Jersey, reported back in 2001 that they had

successfully done similar, giving rise to 15 healthy children who

appeared to be free of their mothers' disease.

Safety check

Instead of transplanting the pronuclei, these researchers injected

another woman's ooplasm - the substance inside the cell that

contains the mitochondrial DNA and bathes the nucleus - into the egg

cell of the mother with faulty mitochondrial DNA.

The UK research, funded by the Muscular Dystrophy Campaign, will

check that transplanting the pro-nuclei works and is safe.

The resulting egg would never be allowed to develop into a baby.

But even if it did, the offspring would still resemble their mother

and father because the mitochondrial DNA does not dictate things

like hair colour.

The researchers stress that this research is only the very first

step in a very difficult process, which they hope will lead to

techniques that might prevent the transmission of mitochondrial DNA

disease.

About one in 5,000 children and adults are at risk of developing a

mitochondrial disease.

The HFEA does not have any regard for public consultation and the

views of the public

phine Quintavalle from Comment on Reproductive Ethics

The group of conditions Professor Turnbull's team will look at is

called mitochondrial myopathy.

These cause muscle weakness and wasting, making it difficult for

those who have it to move normally - some may need to use a

wheelchair.

The Muscular Dystrophy Campaign said it was delighted that the HFEA

had given approval for the research project.

Head of research Dr on said: " The innovative approach

being tested by Professor Turnbull may lead to a treatment for

mitochondrial myopathies, a group of conditions that dramatically

affect quality and length of life. "

The public are currently being consulted about their opinions on

laws governing embryo research such as this.

Some believe it is dangerous and unethical to carry out such work on

human embryos and cells.

Debate

phine Quintavalle from Comment on Reproductive Ethics said she

was horrified.

" This shows once again that the HFEA does not have any regard for

public consultation and the views of the public.

" It is undesirable to create children in this way. It will shock the

world. This is playing around with early human life. "

O¿Gorman, for the charity LIFE, said: " This decision is

utterly unethical, abhorrent and contrary to public opinion.

" The HFEA are relentlessly imposing their libertarian agenda on the

people of this country against their wishes: the government must act

to disband it immediately. "

Professor Turnbull said they were not radically altering an embryo's

DNA.

" We are simply changing the energy source. "

Professor Azim Surani, professor of physiology and reproduction at

Cambridge University, said: " I see few ethical problems as we are

dealing with the embryo at a very early stage where the cells

haven't even started to divide yet. "

Dr Andy Miah, ethicist at Paisley University, said: " Many of the

more controversial ethical concerns arise only if we project into

the future and imagine that a child were to be born, as a result of

this kind of procedure.

" Even if a child were born with 'two mothers', I doubt very much

that we should be concerned about its welfare any more than we are

concerned about the welfare of all children. "