Embryos 'could help treat diseases'

One of the scientists behind a bid to create human-animal embryos has said their work could help treat human diseases.
The Newcastle researchers plan to extract stem cells from embryos that are part cow and part human to see whether they have the potential to treat human diseases.
Future experiments may involve the creation of hybrid human and rabbit embryos.
The application was submitted last year to the Human Fertilisation and Embryology Authority (HFEA), which regulates all embryo research, by the North-east England Stem Cell Institute (NESCI).
They are now waiting for the announcement of the authority's decision on the creation of human-animal embryos, which scientists say will pave the way for therapies for diseases like Parkinson's.
If the authority gives its approval, the institute's application is likely to be heard in November.
A five-strong team of scientists led by Dr Lyle Armstrong plans to carry out the work at the International Centre for Life in Newcastle.
Dr Armstrong, a lecturer at Newcastle University, helped to create the world's first cloned human embryo in 2005.
The research involves transferring nuclei containing DNA from human cells, such as skin cells, to cow eggs.
Before this process is carried out, the cows eggs' own nuclei are removed. However, a certain amount of cow DNA remains in the mitochondria - tiny rod-like power plants that sit outside the nucleus and supply energy.
The resulting cloned embryos are 99.9% human but retain a fraction of animal genes. They are therefore classed as "chimeras" - mixtures of different species.
Stem cells are immature cells that can be programmed to form different kinds of tissue.
Those extracted from embryos - embryonic stem cells - have the potential to become any part of the body, from brain to bone.
In future, they could form the basis of new treatments for a host of diseases, including currently incurable conditions such as Parkinson's, muscular dystrophy and diabetes.
Dr Armstrong said: "At the moment we don't know if the nuclear transfer process works well enough in humans to create useful embryonic stem cells.
"We need to carry out many tests to establish this and, as animal eggs are freely available, it makes sense to use these as a source of material for our laboratory work."
Safeguards are in place to ensure this scientific work stays within British and international law.
"Once we get the go-ahead we will be very strictly monitored by the Human Fertilisation and Embryology Authority," he said.
"We are simply using some of the chemistry of the cow to programme the genes of a human cell."
Within 30 or 40 years it may be possible to grow new human organs from stem cells which are ready for transplant patients.
"Some day it might be possible to produce new human organs in a factory instead of waiting for a donor to become available," Dr Armstrong added.
"The advantage of this over organ transplant is that the recipient would not have to be on drugs for their rest of their life to prevent organ rejection."
Last year teams at Edinburgh University and Kings College London announced plans to seek permission from the HFEA for similar work and also await its decision.