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by Rob Stein
February 01,
2019
from
NPR Website
Dieter Egli,
a
developmental biologist at Columbia University,
and
Katherine Palmerola examine
a newly
fertilized egg injected
with a
CRISPR editing tool.
Rob Stein/NPR
Technocrat scientists at Columbia University are
following China’s lead in editing human embryos
with CRISPR technology.
One lead scientists says,
"Right now we are not trying to make
babies", indicating that they fully intend
to make GMO babies later.
Source
A scientist in New York is conducting experiments designed to modify
DNA in human embryos as a step toward someday preventing inherited
diseases, NPR has learned.
For now, the work is confined to a laboratory. But the research, if
successful, would mark another step toward turning
CRISPR, a powerful form of gene
editing, into a tool for medical treatment.
A Chinese scientist sparked international outrage in November when
he announced that he had used the same technique to create the
world's first gene-edited human babies.
He said his goal was to
protect them from infection with HIV, a claim that was criticized
because there are safe, effective and far less controversial ways of
achieving that goal.
In contrast,
Dieter Egli, a developmental
biologist at Columbia University, says he is conducting his
experiments,
"for research
purposes."
He wants to determine
whether CRISPR can safely repair mutations in human embryos to
prevent genetic diseases from being passed down for generations.
So far, Egli has stopped any modified embryos from developing beyond
one day so he can study them.
"Right now we are not
trying to make babies. None of these cells will go into
the womb of a person," he says.
But if the approach is
successful, Egli would likely allow edited embryos to develop
further to continue his research.
Egli hopes doctors will someday be able edit embryonic human DNA to
prevent many congenital illnesses, such as,
In the lab, Egli is
trying to fix one of the genetic defects that cause
retinitis pigmentosa, an inherited
form of blindness.
If it works, the hope is
that the approach could help blind people carrying the mutation have
genetically related children whose vision is normal.
Egli is attempting to fix
one of the genetic defects
that cause retinitis pigmentosa,
an inherited form of blindness.
Rob Stein/NPR
"Preventing inherited
forms of blindness would be wonderful - very important for
affected families," Egli says.
But that is likely to
take years of additional research to demonstrate that the technique
is both effective and safe.
Nevertheless, even this kind of basic research is controversial.
"This is really
disturbing," says Fyodor Urnov, associate director of the
Altius Institute for Biomedical Sciences
in Seattle.
He worries such
experiments could encourage more irresponsible scientists to misuse
gene-editing technologies.
"As we've learned
from the events in China, it is no longer a hypothetical that
somebody will just go ahead and go rogue and do something
dangerous, reckless, unethical," Urnov says.
Egli's research is
reviewed in advance and overseen by a panel of other scientists and
bioethicists at Columbia.
While the debate over research like Egli's continues,
...and
others are trying to develop
detailed standards for how scientists should safely and ethically
edit human embryos.
Some bioethicists and scientists are calling for an explicit global
moratorium on creating any more gene-edited babies. Others, like
Fyodor Urnov, would like to see a hiatus in even basic research.
The U.S. government prohibits the use of federal funding for
research involving human embryos.
But gene editing of human
embryos can be done using private funding. The Food and Drug
Administration is barred from considering any studies that would
involve using genetically modified human embryos to create a
pregnancy.
But laws that govern the
creation of genetically modified babies vary widely internationally.
Egli is well aware that his work may be controversial to some
people.
To try to be completely
transparent about his experiments, Egli recently invited NPR to his
laboratory for an exclusive look at his research.
"We can't just do the
editing and then hope everything goes right and implant that
into a womb. That's not responsible," Egli says.
"We have to first do
the basic research studies to see what happens. That's what
we're doing here."
To show NPR what he is
doing, early one morning Egli pushes open the door of a tiny
windowless room on the sixth floor of one of Columbia's research
towers in Upper Manhattan.
The lab is jammed with
scientific equipment, including two microscopes.
Egli snaps on blue rubber gloves and opens a frosty metal cylinder
holding frozen human eggs.
"I'm going to wear
gloves because we want to keep things clean," he tells me.
To begin his experiment,
Egli starts the long, slow process of thawing the frozen human eggs
that were donated for research.
After several hours of
careful work and waiting, Egli has readied 15 eggs for his
experiment.
After setting up a large microscope, Egli slides a round glass dish
under the lens. The dish contains sperm from a blind man who carries
the mutation that Egli is trying to fix.
It also holds the CRISPR
gene-editing tool.
"I'm starting with
just one egg," he says as he gently places the first thawed egg
into the dish.
"It's a beautiful cell," Egli says, pointing to a magnified
image of the egg on a computer monitor. "I would say it's one of
the most beautiful cells."
Egli maneuvers a tiny
glass needle protruding into the side of the microscope dish toward
one of the sperm.
"So you can see a
moving sperm over here," he says. "Now I'm picking it up. The
sperm is in the needle. Now I'm dipping it in the CRISPR tool."
Once the sperm is inside
the needle with the CRISPR gene-editing tool, Egli points the
needle's tip at the egg.
"Oh no!" he exclaims
with a sigh. "The sperm is swimming away."
He searches the dish for
the errant sperm.
"Oh, here it is," he
says as he pulls the sperm back into the needle.
Next, Egli gently pierces
the egg with the needle.
"The membrane is
broken - breached. There we go," Egli says as he injects the
sperm and CRISPR tool into the egg.
He breathes a sigh of
relief.
Egli injects a human egg
with a sperm carrying a genetic mutation
that causes blindness and
a CRISPR tool he hopes will fix the mutation.
Rob Stein/NPR
The idea is that CRISPR will slice out the mutation in the sperm,
and the healthy DNA in the egg will serve as a template to repair
the genetic mutation.
"Hopefully the CRISPR
tool will cut the mutation and then the egg will replace that
with a version that no longer causes disease," Egli says.
"The genome from the
mother would be rescuing the mutant genome from the father."
The approach was
developed by scientists led by
Shoukhrat Mitalipov of the
Oregon Health & Science University in Portland.
Egli was initially skeptical of the
Oregon group's claims that they had
used CRISPR for the first time to repair a mutation in human embryos
this way. Egli's research is aimed at trying to confirm that it
works and how.
Mitalipov's group is also continuing to study the technique to see
whether it can safely fix several genetic mutations in human
embryos, including one of the breast cancer genes.
For the next two hours, Egli painstakingly fertilizes and edits one
egg after another. He has to overcome a variety of technical
complications.
At one point, the tip of
the fragile needle unexpectedly breaks off at a crucial moment.
"There we go," he
says later, after the needle is replaced. "That one definitely
worked. Beautiful."
This work may be
beautiful to Egli, but it makes critics very nervous.
"Anyone with a
connection to the Internet will be able to download the recipe
to make a designer baby," Urnov says. "And then the question
becomes:
'What's to
prevent them from using it?'
As we learned in the
past year: apparently nothing."
So Urnov worries about
any such research proceeding.
"We need to hit the
pause button and keep it pressed until we understand how do we
proceed in a way that minimizes the risk of people going rogue,"
Urnov says.
Urnov and others argue
society needs a much broader debate about whether there is a truly a
compelling reason to ever try to make any more gene-edited babies.
There are many other ways
to prevent genetic diseases, they note.
"If we've learned
anything from what's happened in China, it's that the urge to
race ahead pushes science to shoot first and ask questions
later," says
J. Benjamin Hurlbut, an
associate professor of biology and society at Arizona State
University.
"But this is a domain
where we should be asking questions first. And maybe never
shooting. What's the rush?"
That's especially true
when the prospect of creating gene-edited babies raises so many
fraught ethical questions, including fears that it could eventually
lead to the creation of "designer babies," critics say.
"We don't need to be
mucking around with the genes of future children," says
Marcy Darnovsky, director of
the Center for Genetics and Society, a watchdog group.
"This could open the
door to a world where people who were born genetically modified
are thought to be superior to others, and we would have a
society of people who are considered to be genetic haves and
genetic have-nots."
But many other scientists
and bioethicists disagree.
"This is valid
research, and I think it's important research," says
R. Alta Charo, a bioethicist at
the University of Wisconsin, Madison.
"It has value not
only for the possible use in the future for some number of
conditions that would involve a live birth, but it has value for
basic understanding of embryology, basic understanding of
development," Charo says.
"Of course I think we
should be doing that research. Why wouldn't you be doing that
research?"
Many leading scientists
agree.
"Is there value in
doing that kind of research? I think there is," agrees
Jennifer Doudna, a biochemist
at the University of California, Berkeley, who helped invent
CRISPR.
"Does it have to be
carried out carefully and under the right regulatory guidelines?
Of course. But I think there's value in doing research like
that."
"I'd like to see the U.S. be involved and show leadership on how
to do that responsibly rather than say we're not going to have a
seat at the table," Doudna says.
Back in Egli's lab, it's
now nearly 3 p.m., and he is wrapping up the day's experiments.
"OK, that's it.
That's the last one," he says as he places back into storage the
last of 14 eggs he managed to fertilize and hopefully edit.
He will stop their
development the next morning to see whether it worked...
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