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Q&A: Hybrid embryos Q&A: Hybrid embryos
(about 2 hours later)
Early embryos yield stem cellsA bill is going through Parliament which would allow scientists to create human-animal embryos for research.Early embryos yield stem cellsA bill is going through Parliament which would allow scientists to create human-animal embryos for research.
Researchers say the work is needed to advance the understanding of complex diseases such as Parkinson's, Alzheimer's and Motor Neurone Disease.Researchers say the work is needed to advance the understanding of complex diseases such as Parkinson's, Alzheimer's and Motor Neurone Disease.
But critics say it involves the needless destruction of human life, and is fraught with moral difficulties.But critics say it involves the needless destruction of human life, and is fraught with moral difficulties.
What is a hybrid?What is a hybrid?
The experiments involves transferring nuclei containing DNA from human cells, such as skin cells, into animal eggs that have had almost all of their genetic information removed.The experiments involves transferring nuclei containing DNA from human cells, such as skin cells, into animal eggs that have had almost all of their genetic information removed.
The resulting cytoplasmic embryos are more than 99% human, with a small animal component, making up around 0.1%. The resulting cytoplasmic embryos - known as admixed embryos - are more than 99% human, with a small animal component, making up around 0.1%.
The embryo would be grown in the lab for a few days, then harvested for stem cells - immature cells that can become many types of tissue.The embryo would be grown in the lab for a few days, then harvested for stem cells - immature cells that can become many types of tissue.
Why use animal eggs?Why use animal eggs?
The creation of hybrid human-animal embryos was first suggested as a way of addressing the shortage of human eggs available for research.The creation of hybrid human-animal embryos was first suggested as a way of addressing the shortage of human eggs available for research.
Also, experts say using human-animal mixes rather than human eggs to get the stem cells makes sense because the process is less cumbersome and yields better results.Also, experts say using human-animal mixes rather than human eggs to get the stem cells makes sense because the process is less cumbersome and yields better results.
How could this help find disease cures?How could this help find disease cures?
Scientists say they can use embryonic stem cells to study different disease processes.Scientists say they can use embryonic stem cells to study different disease processes.
For example, they could take genetic material from a person with Parkinson's disease and put it into an empty animal egg to make stem cells that will carry the same genetic defects that cause Parkinson's.For example, they could take genetic material from a person with Parkinson's disease and put it into an empty animal egg to make stem cells that will carry the same genetic defects that cause Parkinson's.
Stem cells also have the potential to grow into different tissues, so in the future it might be possible to transplant cells cloned from individual patients to cure diseases.Stem cells also have the potential to grow into different tissues, so in the future it might be possible to transplant cells cloned from individual patients to cure diseases.
What are the concerns about the work?What are the concerns about the work?
Opponents say this is tampering with nature and is unethical.Opponents say this is tampering with nature and is unethical.
Critics say they are repulsed by the idea and there must be no creation of an animal-human hybrid.Critics say they are repulsed by the idea and there must be no creation of an animal-human hybrid.
It is already illegal to implant human-animal embryos in the womb or bring them to term.It is already illegal to implant human-animal embryos in the womb or bring them to term.
One of the scientists applying to do hybrid work, Professor Chris Shaw from Kings College London, stressed: "We think there is nothing illegal, immoral or unethical about this.One of the scientists applying to do hybrid work, Professor Chris Shaw from Kings College London, stressed: "We think there is nothing illegal, immoral or unethical about this.
"While we understand the concerns, we think they are largely founded on misinformation."While we understand the concerns, we think they are largely founded on misinformation.
"People think we are generating some sort of hybrid animal. This is just cells, just for science. No animal is ever going to be created.""People think we are generating some sort of hybrid animal. This is just cells, just for science. No animal is ever going to be created."
What does the law say?What does the law say?
Although ministers felt the Human Fertilisation and Embryology Act 1990 needed updating as science had moved on significantly, they were initially cool on the idea of creating human-animal embryos.Although ministers felt the Human Fertilisation and Embryology Act 1990 needed updating as science had moved on significantly, they were initially cool on the idea of creating human-animal embryos.
However, they bowed to pressure from scientists, who argued a ban would hamper medical research.However, they bowed to pressure from scientists, who argued a ban would hamper medical research.
In addition, the House of Commons Science and Technology Committee carried out an inquiryinto the proposals and concluded that the creation of hybrid embryos was necessary for research and that there should not be a complete ban.In addition, the House of Commons Science and Technology Committee carried out an inquiryinto the proposals and concluded that the creation of hybrid embryos was necessary for research and that there should not be a complete ban.
A draft bill published in May 2007 allows for the creation of human embryos that have been physically mixed with one or more animal cells. However, true human-animal hybrids, made by the fusion of sperm and eggs, would remain outlawed.A draft bill published in May 2007 allows for the creation of human embryos that have been physically mixed with one or more animal cells. However, true human-animal hybrids, made by the fusion of sperm and eggs, would remain outlawed.
Will the bill become law?Will the bill become law?
Opponents are determined to block the proposals. Several leading members of the Catholic Church have described them as immoral.Opponents are determined to block the proposals. Several leading members of the Catholic Church have described them as immoral.
In his Easter sermon, Cardinal Keith O'Brien, leader of the church in Scotland, described the legislation as a "monstrous attack on human rights, human dignity and human life".In his Easter sermon, Cardinal Keith O'Brien, leader of the church in Scotland, described the legislation as a "monstrous attack on human rights, human dignity and human life".
A significant number of MPs, including several Catholic members of the Cabinet, are also reported to have serious concerns about the legislation, leading to speculation of high profile resignations.A significant number of MPs, including several Catholic members of the Cabinet, are also reported to have serious concerns about the legislation, leading to speculation of high profile resignations.
Prime Minister Gordon Brown has promised that MPs will be given a free vote on some of the more controversial aspects of the bill, including human-animal embryos.
But some 200 medical charities have urged MPs to support legislation allowing the creation of animal-human embryos.But some 200 medical charities have urged MPs to support legislation allowing the creation of animal-human embryos.
And Labour peer and fertility expert Lord Winston has accused the church of misleading the public over the issue.And Labour peer and fertility expert Lord Winston has accused the church of misleading the public over the issue.
Will the scientists be able to proceed with their work?Will the scientists be able to proceed with their work?
The body that grants licences for embryo research, the Human Fertilisation and Embryology Authority, has agreed in principle to the creation of human-animal hybrids.The body that grants licences for embryo research, the Human Fertilisation and Embryology Authority, has agreed in principle to the creation of human-animal hybrids.
However, it also stressed that each application must be considered closely on its own merits.However, it also stressed that each application must be considered closely on its own merits.
If future government legislation differs from the HFEA line, then the regulator will be forced to rethink.If future government legislation differs from the HFEA line, then the regulator will be forced to rethink.