Wednesday, September 28, 2016
The world’s first child created using a controversial
new "three-parent" baby technique has been born in Mexico.
Scientists
say the technique combines DNA from three people - the mother, father
and an egg donor. Limited details about the birth were revealed ahead of
the American Society of Reproductive Medicine's scientific congress in Salt Lake City next month, where it will be discussed more fully.
According to critics, the procedure is tantamount to genetic
modification of humans or even “playing God”. But supporters say it
allows women with a particular type of genetic disease to have healthy
children who are related to them.
The magazine New Scientist, said the
baby was now five months told and born to Jordanians parents. The work
was carried out by a team of experts from the US led by Dr. John Zhangof
of the New Hope Fertility Center in New York. The goal was to prevent
the baby from inheriting a fatal genetic disease from his mother, who
had previously lost two children to the illness.
The child’s mother has Leigh syndrome, a fatal disorder that
affects the developing nervous system and would have been passed on in
her mitochondrial DNA.
Although she is healthy, two of her children have died as a
result of inheriting the disease: a girl who lived until she was six and
an eight-month-old baby. The research summary identified the mother as 36-year-old and
said her pregnancy was uneventful. One of the five eggs the researchers
treated was suitable for use.
The technique used by Dr John Zhang and his team involved removing some of the mother’s DNA from an egg,
and leaving the disease-causing DNA behind. The healthy DNA was slipped
into a donor’s egg, which was then fertilized. As a result, the baby
inherited DNA from both parents and the egg donor.
The
technique is sometimes said to produce “three-parent babies,” but the
DNA contribution from the egg donor is very small. People carry DNA in
two places, the nucleus of the cell and in
features called mitochondria, which lie outside the nucleus. The
technique is designed to transfer only DNA of the nucleus to the donor
egg, separating it from the mother’s disease-causing mitochondrial DNA.
Critics question the technique’s safety, saying children would have
to be tracked for decades to make sure they remain healthy. And they say
it passes a fundamental scientific boundary by altering the DNA
inherited by future generations. Mitochondrial DNA is passed from women
to their offspring.
Still, last year, Britain became the first country in the world to
allow creation of human embryos with the technique. In the U.S., a panel
of government advisers said earlier this year that it’s ethical to test
the approach in people if initial experiments follow certain strict
safety steps.
That report was requested by the Food and Drug Administration, which
is currently prevented by Congress from considering applications to
approve testing the technique in people.
Shroukhrat Mitalipov, who has worked with the approach at the Oregon
Health & Science University in Portland, said that given the panel’s
conclusion,
"We believe it’s time to move forward with FDA-approved
clinical trials in the United States."
Henry Greely, who directs the Center for Law and the Biosciences at
Stanford University, said Tuesday
he sees nothing wrong with using the
technique if it is safe and is aimed at diseases clearly caused by
faulty mitochondrial DNA. But he called the research leading to the
newly reported birth "unethical, unwise, immoral." He said the approach
“hasn’t been
sufficiently proven safe enough to try to use to make a baby."
Dieter Egli of the New York Stem Cell Foundation, who has done work
in the area, was cautious about the implications of the new report.
"I wouldn’t go out there at this point and tout the accomplishment
because we don’t have enough information,” he said Tuesday. “We do not
know exactly what was done. We have to wait for a fuller report," he said.
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