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A controversial scientist, who failed in his attempts to clone a human in January, has met further scepticism over his latest cloning claims.
US fertility doctor Panos Zavos says he has created a cloned embryo using tissue from dead people.
Experts said such actions would exploit the vulnerability of grieving people who had been bereaved.
And the Royal Society also questioned "a lack of evidence" behind Dr Zavos' claims.
Dr Zavos told a press conference in London he had successfully combined genetic material from three dead people with cow eggs to make embryos that were an identical copy of the deceased.
He said he took DNA from blood samples from an 11-year-old girl who had died three days earlier in a car crash.
The other corpses whose tissue he took included an18-month-old toddler who had died following surgery, and a 33-year-old man.
Two of the three experiments were successful, creating embryos that Dr Zavos claimed would be "potentially viable" if left to grow in the human womb.
Dr Zavos said he had not done this yet and had stopped the embryos' development at an early stage when cells begin to divide and multiply rapidly.
But he said his current work was a major step forward, showing this could be a way to clone humans in the future.
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Stem cell research rapidly expands under government incentives
SINGAPORE (Reuters) -- Singapore banned human cloning on Thursday and said offenders would face 10 years in jail to prevent "abhorrent experiments."
Singapore is a science hub with some of the world's most liberal rules on stem cell research and aims to boast 15 world-class biotechnology companies by 2010 after pouring at least $1.8 billion into life sciences.
"There is almost unanimous agreement from the international community, local scientific and religious groups as well as our general public that reproductive cloning of human beings is abhorrent," junior health minister Balaji Sadasivan told parliament while passing the law.
The government raised the jail term for human cloning from a proposed 5 years after public pressure.
The law, part of a series of regulations to govern a nascent biomedical research industry, specifically bans placing any human embryo clone in the body of a human or the body of an animal.
It also prohibits developing a human embryo outside the body of a woman for more than 14 days. Any person found guilty of cloning activity could also be fined up to S$100,000 ($58,000).
But in keeping with Singapore's relatively liberal attitude towards human stem cell research, the legislation allows therapeutic cloning, or the creation of cloned embryos for the purpose of harvesting stem cells.
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The public has hardened its stance against genetically modified foods, according to a new survey.
More than six out of 10 people (61 per cent) polled on behalf of the consumer magazine Which? said they were concerned about the use of GM material in food production - up from 56 per cent in 2002.
The survey of almost 1,000 people also recorded a rise in the number who said they tried to avoid GM food and a fall in the percentage who backed the widespread growth of GM crops in Britain.
Malcolm Coles, editor of Which?, said: "Consumers clearly don't want GM food and are hardening their stance against it. It's hardly surprising when questions still remain about the risks for health and the environment.
"The Government has ignored public opinion on this subject for long enough. It needs to rethink its policy before going ahead with growing GM crops commercially."
The Government approved the commercial growing of one variety of genetically-modified maize earlier this year.
Margaret Beckett, the Environment Secretary, gave qualified approval to the herbicide-tolerant maize for animal feed but rejected commercial cultivation of GM beet and oilseed rape.
The Which? survey saw a 13 per cent rise in the number of people who said they tried to avoid GM food and ingredients, up from 45 per cent in 2002 to 58 per cent.
Just over a quarter back the growing of GM crops in the UK, down from 32 per cent two years ago. However, there was a rise in the number of people satisfied manufacturers are removing GM from their food, up from 28 per cent to 33 per cent.
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BOSTON - Police yesterday arrested a man in connection with last week's pipe bomb explosion at a Boston-area laboratory specializing in stem-cell research.
The man already had been charged last year with trying to blow up the same building.
The pipe bomb exploded last Thursday morning at the Amaranth Bio laboratory in Watertown, Mass., shattering windows, police said. No one was hurt.
Watertown police said they arrested Brad Karger, 29, yesterday morning. He will be arraigned on charges of having placed an explosive device and burning a building.
Police said Karger was awaiting trial on charges he tried to cause a gas explosion in the same building in February 2003.
Efforts to reach Karger and his lawyer were not immediately successful.
Amaranth Bio's Web site says that its technology is focused on organ regeneration and that it is working on possible cures for diabetes and liver disorders.
The FBI and the Bureau of Alcohol, Tobacco, Firearms and Explosives also joined the investigation.
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–-MARTIN ENSERINK and JOCELYN KAISER
Worries about the avian influenza strain, H5N1, that's circulating in Asia have ratcheted up another notch. A paper published online by Science today confirms that the virus can infect cats, and that felines can transmit the virus to other cats as well--and perhaps to humans. Cats' vulnerability to H5N1--which comes on the heels of similar findings in pigs--increases concerns that the virus may evolve into a more dangerous strain that could set off an influenza pandemic.
H5N1 has ravaged poultry farms in nine Asian nations and has claimed the lives of at least 26 people. The virus was first reported in cats in January, when a clouded leopard at a zoo near Bangkok died from an infection; a month later, a sick white tiger at the same zoo tested positive for H5N1. Eating raw, infected poultry was the likely infection route.
To further investigate cats' susceptibility, Thijs Kuiken, a veterinary pathologist at Erasmus University in Rotterdam, the Netherlands, and colleagues inoculated the tracheas of three young domestic cats with H5N1 isolated from a fatal human case. All developed flu symptoms, such as fever and labored breathing, and one died after 6 days. Necropsy of the sick cats revealed lung tissue damage similar to that caused by H5N1 in humans. Two cats living in close contact with an infected animal also became sick, as did three others that each ate an H5N1-infected chick.
The study underscores H5N1's ability to infect multiple mammal species, which is unusual for strains that circulate in birds. Indeed, just 2 weeks ago, director Chen Hualan of China's National Avian Influenza Reference Laboratory in Harbin announced at a meeting in Beijing that H5N1 had also been found to infect pigs as early as last year, a finding that was first reported in January in a Chinese journal. Those results are especially worrisome, flu experts say, because pigs are believed to be mixing vessels in which avian and human flu viruses can combine into new strains.
Klaus Stöhr, a virologist at the World Health Organization in Geneva, Switzerland, says there’s no indication so far that H5N1 has become established in pig populations. That's no cause for complacency, however, adds Stöhr, who urges countries where H5N1 has been found to step up surveillance of pigs. And cats with access to poultry should be watched for signs of illness, says Stöhr.
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WASHINGTON (Reuters) - Master cells found deep inside hair follicles might offer a new way to treat baldness and burn victims, U.S. researchers reported on Thursday.
So far the cells have only been found in mice but there is no reason to believe they do not also exist in humans, the team at the Howard Hughes Medical Institute and The Rockefeller University in New York said.
The cells, known as stem cells, replace not only hair but also stretches of skin and sebaceous glands, key to healthy skin and hair, the researchers report in this week's issue of the journal Cell.
In this case the stem cells the researchers found are adult stem cells -- immature master cells that retain the ability to change their "type" to some degree.
They are different from stem cells taken from embryos, a more controversial source.
"We've identified cells within skin that bear all the characteristics of true stem cells -- the ability for self-renewal and the multipotency required to differentiate into all lineages of epidermis and hair," said Elaine Fuchs, a cell biologist at Rockefeller who led the study.
"This is the first work that indicates a single skin stem cell can generate both epidermis and hair, even after propagation in the lab," she added.
Fuchs and colleagues now want to look for similar hair follicle stem cells in people.
"With debate about the cells' multipotency within skin tissue settled, we can now ask whether the stem cells can also make other cell types in addition to hair and skin," Rockefeller's William Lowry said in a statement.
"These results open the door to that possibility."
The stem cells multiplied well in laboratory dishes and when the researchers grafted the cells onto the backs of bald mice, they grew tufts of hair and skin.
Previous work had used genetic manipulation to find the stem cells in the mice but Fuchs and colleagues found a better way to identify the scarce stem cells.
"We found that the surface of the skin stem cells was different than the other cells of the skin, enabling us to use two different antibodies to sort them out from the other skin cells," said Lowry. "No one had been able to isolate stem cells from the hair follicle in this way before."
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