Wednesday, January 19, 2011

Dr. Frankenstein is Still Hard at Work Building Yet Another Monster

A human egg is manipulated during IVF treatment. The two experimental techniques scientists want to try are maternal spindle transfer and pronuclear transfer. Photograph: Getty Images/Science Photo Library

Here it is, ladies and gentlemen...the thin edge of the wedge. Leading research organisations and patient groups are asking the government to change the law to allow scientists to implant embryos that have genetic material from three different parents into a select group of women. This group of women will be women with specific defects in their mitochondrial DNA.

Call me a pessimist; but, I see a world of legal problems opening up here. What rights does the third parent have surrounding custody, visitation, financial responsibilities; and, a host of other previously unexplored moral, ethical and legal dilemmas? How will the DNA necessary from this third party be harvested? Who will supply the demand?

So far, the procedure has only been tried in the lab using animal embryos. However, if the three-parent technique proves safe and successful in the lab, scientists expect that it could prevent several hundred babies being born with genetic defects every year when used with human embryos.

Mitochondrial DNA diseases can include many symptoms: poor growth, loss of muscle coordination, muscle weakness, visual problems, hearing problems, learning disabilities, mental retardation, heart disease, liver disease, kidney disease, gastrointestinal disorders, respiratory disorders, neurological problems, autonomic dysfunction, and dementia. Many babies die as a result of these genetic defects.

Mitochondrial DNA is found only in the egg of the mother. Mitochondria are located in every human cell and act as "power houses" to provide the energy for cells to function. Yet mitochondrial DNA is not present in the nucleus of a fertilised egg, meaning scientists could extract the nucleus and place it into another egg from a donor.

The resulting embryo would have almost 100% inherited genetic material from its mother and father; but, would still have some DNA from the donor egg no matter how tiny an amount.

British scientists have led efforts to find ways to prevent inherited disorders being passed on and causing babies to die or be disabled. The call for a law change comes in a letter sent to Andrew Lansley, the health secretary. The letter, from the Wellcome Trust, Academy of Medical Sciences, Medical Research Council and Muscular Dystrophy Campaign, among others, was dispatched as a group of experts published a review commissioned by Lansley into the safety and effectiveness of scientific procedures attempted so far.

Two separate techniques have been explored by scientists, both of which involve mixing the DNA of the parents with a small amount of mitochondrial DNA from a donor egg.

This is not, however, "three-parent IVF", said Professor Robin Lovell-Badge, one of the authors of the review which has now gone to the government. "It is not a term we have used once in this report and it is not a term that should be used," he said. "This is a tiny, tiny bit of DNA. It is not carrying any characteristics except that you have normally functioning mitochondria."

I don't see how this can be called anything other than "three-parent IVF". The DNA of a couple wanting to have a child is mixed with some of the mitochondrial DNA of another woman. A child that is a product of this technique can not be brought about without the help of the DNA of a third person. In my mind, this gives the child three parents.

The scientists involved contend that the DNA contribution from the egg with normal mitochondria is tiny compared to the DNA from the two main parents. I contend that no matter how tiny the third-party DNA is still present.

Dr Evan Harris, the former Lib Dem MP who has taken a close interest in embryo research, likened it to "changing the battery on the laptop, but not affecting the information on the hard disk". A rather callous opinion, in my opinion.

The review (pdf), under the auspices of the Human Fertilisation and Embryology Authority, found that the scientific procedures appeared to be safe and effective; but, recommended that three further experiments should take place.

"Some people seem to be taking our report as negative and hesitant - it wasn't meant to be at all," said Lovell-Badge. "It was meant to say, just gather a little bit more information."

One of the two experimental techniques is called maternal spindle transfer (I just love these large attention-shifting euphemisms) and involves removing the genetic material from the would-be mother's unfertilised egg and fusing it into a donor egg from which the nucleus has been removed. Fertilisation with the partner's sperm takes place afterwards.

"It's been done in various animals and seems to be both efficient and safe," said Lovell-Badge. The scientists would now like to try it out on human volunteers. But what if something goes wrong? If during the pregnancy, birth or early days something is discovered to be drastically - possibly irreparably - amiss. What then? Do we abort or euthanize this innocent and move on to attempt #469?

The other method is pronuclear transfer, which has been researched by the Institute of Genetic Medicine at Newcastle University. This involves the transfer of both parents' DNA from a fertilised egg into a fertilised donor egg which has had its nucleus removed. Depending on your stand surrounding the beginning of life - conception or birth - this could prove to be a Pandora's box of moral, ethical and spiritual wranglings.

This was successfully carried out in mice as early as the 1980s; and, in Newcastle experiments have also been done with abnormal human eggs.

The further experiments should not take much more than a year. Scientists and patient groups are now pressing the government to consider the legal and ethical issues involved, so that the necessary regulatory changes can be made to move the experimental work into the clinic as soon as possible.

In the meantime, has anyone given any thought to the lives we are creating on an experimental basis. Animals are not humans and should not be used for experimentation because the statistics are based on animal physiology not human. What is the plan if a life is created using this method and health issues - possibly extremely painful or life-threatening - become apparent in middle-age or later life?

I don't think we have the right to take these kinds of chances with other peoples' lives. OK...soapbox back under the bed. I'm ready for the cards and letters.


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