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SINGAPORE - A fish named Holly may have placed Singapore on the world map for being the birthplace of the very first semi-cloned animal.
By combining the stem cell of an embryo - one which is created to contain only one set of chromosomes - with an egg which provides the other set, three National University of Singapore (NUS) researchers were able to create a fish that is not an exact clone.
In traditional cloning, a baby is formed from a stem cell with two sets of chromosomes from one parent, making it an exact duplicate - and spawning great debate about the ethics of cloning since the world's first animal, Dolly the sheep, was cloned from an adult stem cell in 1996.
Now, the successful birth of the first semi-cloned animal, Holly the fish, means researchers can possibly use semi-cloning as a method to treat infertile couples.
Associate Professor Hong Yunhan, who led the research team from the National University of Singapore Department of Biological Sciences, said semi-cloning is better than cloning, as it produces babies in an "unpredictable" way.
"We can't even predict whether the offspring is a male or female," said Assoc Prof Hong.
What is needed, for instance, could be for a man without mature sperm to use stem cells - which can later develop into all other kinds of cells - from another part of his body, to fuse with his wife's egg.
But it may take as long as 10 years to get to the stage where the technique can be researched in humans, said Assoc Prof Hong, who added that the semi-cloning technique can also be used to study diseases by analysing gene mutations.
His five-year research programme, funded by NUS, the Agency for Science, Technology & Research (A*Star) and the Ministry of Education, has so far cost $1.5 million. Assoc Prof Hong estimates he needs between $5 and $10 million more to further the work.
His team of researchers will now look at semi-cloning mice, monkeys and, eventually, humans - if possible.
But could this technique spark off a new debate about cloning? Most likely not, said Dr Alan Colman, the creator of Dolly.
Dr Colman, who is the executive director of A*Star's Singapore Stem Cell Consortium, told MediaCorp that producing an offspring by semi-cloning is "less provocative, even if it could be extended to the human condition".
"Because the eggs are all different, every animal born to the technique will be genetically distinct," he said, comparing it to the cloning process of removing the entire nucleus of an egg and replacing it with the embroyonic stem cell of only one donor.
In semi-cloning, the nucleus of a donor's embryonic stem cell is introduced into the host using microneedles while still keeping the egg's nucleus - a process called nuclear transfer.
However, Professor Lim Pin, chairman of the Bioethics Advisory Committee, noted that semi-cloning is still a form of cloning, and the technology will come under regulation in Singapore if it is used on humans.
And while the research potential using animals to study diseases or treatments may be promising, there are ethical issues like the meaning of parenthood if the techniques are extended to human embryos and humans, said Archbishop John Chew, president of the National Council of Churches of Singapore.
Father James Yeo from St Anne's Church told MediaCorp: "The Catholic Church has no objection to the cloning of plants and animals as long as these technologies are not harmful to the environment and do not pose any disproportionate risks to human life."
But he reiterated that cloning of humans is not ethically acceptable, no matter what technology is used. "It (cloning) violates human dignity and dilutes the meaning of personhood. It could eventually blur the line of parentage and is open to all kinds of abuses," said Father James.
- TODAY/ir
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