UK approves therapeutic cloning

The green light was given to scientists from the Centre for Life at Newcastle University, northern England, who aim to use the stem cells cloned to treat serious diseases.

Cloning humans for reproductive purposes remains illegal and is punishable by a 10-year prison sentence and unlimited fines.

British researchers say it is likely to be at least five years before clinical trials start and it could be many more years before embryonic stem cell treatments are available to patients.

Stem cell technology is intended to create material that could one day treat diabetes, cancer, Alzheimer’s disease and other disorders, and not to make a cloned child, scientists said.

The Vatican has reiterated its opposition to human cloning. Spokesman Joaquin Navarro-Valls said: “The Holy Father has always unequivocally condemned all forms of human cloning, even for therapeutic purposes”.

Stem cells are nascent cells that can be stimulated by chemical signals in the body into becoming different kinds of tissue.

The most versatile of these are stem cells that come from embryos, as these cells can grow into almost any part of the body.

Therapeutic cloning researchers are hoping that stem cells will eventually be able to grow replacement tissue in a lab dish. These tissues – for example, brain cells, skin, liver, or a kidney – could be used for human transplants.

As decades of conventional organ transplants have shown, transplanted tissue is invariably rejected as foreign by the patient’s immune system if it comes from another body.

It is assumed that cloned embryonic stem cells – stem cells which have exactly the same DNA as the patient – would be accepted by his or her body as friendly rather than hostile tissue.

The cloning technique to be used at Newcastle’s Centre for Life involves removing the nucleus of a human egg cell and replacing it with the nucleus from a human body cell, such as a skin cell.

The egg is then artificially stimulated causing it to divide and behave in a similar way to a standard embryo fertilised by sperm.

The embryos would be destroyed before they were 14-days old and would not be allowed to develop beyond a cluster of cells the size of a pinhead.

The eggs used are those left over from in-vitro fertilisation (IVF) treatment.

Such research is denounced by a host of conservative and religious groups who argue scientists are destroying human life in the course of their experiments.

These detractors believe alternatives such as using adult stem cells should be more vigorously examined and question where this present research could lead.

Britain has played an important role in cloning technology. Its scientists created Dolly the sheep, the world’s first mammal to be cloned from an adult cell.

In February 2003, Dolly was put down after a veterinary examination showed she had a progressive lung disease.

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