ZCZC
BFF-20
YEAR2019-GENETICS-THERAPY-RESEARCH
2019: the year gene therapy came of age
WASHINGTON, Dec 5, 2019 (BSS/AFP) – In the summer, a mother in Nashville
with a seemingly incurable genetic disorder finally found an end to her
suffering — by editing her genome.
Victoria Gray’s recovery from sickle cell disease, which had caused her
painful seizures, came in a year of breakthroughs in one of the hottest areas
of medical research — gene therapy.
“I have hoped for a cure since I was about 11,” the 34-year-old told AFP
in an email.
“Since I received the new cells, I have been able to enjoy more time with
my family without worrying about pain or an out-of-the-blue emergency.”
Over several weeks, Gray’s blood was drawn so doctors could get to the
cause of her illness — stem cells from her bone marrow that were making
deformed red blood cells.
The stem cells were sent to a Scottish laboratory, where their DNA was
modified using Crispr/Cas9 — pronounced “Crisper” — a new tool informally
known as molecular “scissors.”
The genetically edited cells were transfused back into Gray’s veins and
bone marrow. A month later, she was producing normal blood cells.
Medics warn that caution is necessary but, theoretically, she has been
cured.
“This is one patient. This is early results. We need to see how it works
out in other patients,” said her doctor, Haydar Frangoul, at the Sarah Cannon
Research Institute in Nashville.
“But these results are really exciting.”
In Germany, a 19-year-old woman was treated with a similar method for a
different blood disease, beta thalassemia. She had previously needed 16 blood
transfusions per year.
Nine months later, she is completely free of that burden.
For decades, the DNA of living organisms such as corn and salmon has been
modified.
But Crispr, invented in 2012, made gene editing more widely accessible. It
is much simpler than preceding technology, cheaper and easy to use in small
labs.
The technique has given new impetus to the perennial debate over the
wisdom of humanity manipulating life itself.
“It’s all developing very quickly,” said French geneticist Emmanuelle
Charpentier, one of Crispr’s inventors and the cofounder of Crispr
Therapeutics, the biotech company conducting the clinical trials involving
Gray and the German patient.
MORE/FI/ 1041 hrs
ZCZC
BFF-21
YEAR2019-GENETICS-THERAPY-RESEARCH-2-LAST
– Cures –
Crispr is the latest breakthrough in a year of great strides in gene
therapy, a medical adventure started three decades ago, when the first TV
telethons were raising money for children with muscular dystrophy.
Scientists practising the technique insert a normal gene into cells
containing a defective gene.
It does the work the original could not — such as making normal red blood
cells, in Victoria’s case, or making tumor-killing super white blood cells
for a cancer patient.
Crispr goes even further: instead of adding a gene, the tool edits the
genome itself. After decades of research and clinical trials on a genetic fix
to genetic disorders, 2019 saw a historic milestone: approval to bring to
market the first gene therapies for a neuromuscular disease in the US and a
blood disease in the European Union.
They join several other gene therapies — bringing the total to eight —
approved in recent years to treat certain cancers and an inherited blindness.
Serge Braun, the scientific director of the French Muscular Dystrophy
Association, sees 2019 as a turning point that will lead to a medical
revolution.
“Twenty-five, 30 years, that’s the time it had to take,” he told AFP from
Paris.
“It took a generation for gene therapy to become a reality. Now, it’s only
going to go faster.”
Just outside Washington, at the National Institutes of Health (NIH),
researchers are also celebrating a “breakthrough period.”
“We have hit an inflection point,” said Carrie Wolinetz, NIH’s associate
director for science policy.
These therapies are exorbitantly expensive, however, costing up to $2
million — meaning patients face grueling negotiations with their insurance
companies.
They also involve a complex regimen of procedures that are only available
in wealthy countries.
Gray spent months in hospital getting blood drawn, undergoing
chemotherapy, having edited stem cells reintroduced via transfusion — and
fighting a general infection.
“You cannot do this in a community hospital close to home,” said her
doctor.
However, the number of approved gene therapies will increase to about 40
by 2022, according to MIT researchers.
They will mostly target cancers and diseases that affect muscles, the eyes
and the nervous system.
– Bioterrorism – Another problem with Crispr is that its relative
simplicity has triggered the imaginations of rogue practitioners who don’t
necessarily share the medical ethics of Western medicine.
Last year in China, scientist He Jiankui triggered an international
scandal — and his excommunication from the scientific community — when he
used Crispr to create what he called the first gene-edited humans.
The biophysicist said he had altered the DNA of human embryos that became
twin girls Lulu and Nana.
His goal was to create a mutation that would prevent the girls from
contracting HIV, even though there was no specific reason to put them through
the process.
“That technology is not safe,” said Kiran Musunuru, a genetics professor
at the University of Pennsylvania, explaining that the Crispr “scissors”
often cut next to the targeted gene, causing unexpected mutations.
“It’s very easy to do if you don’t care about the consequences,” Musunuru
added.
Despite the ethical pitfalls, restraint seems mainly to have prevailed so
far.
The community is keeping a close eye on Russia, where biologist Denis
Rebrikov has said he wants to use Crispr to help deaf parents have children
without the disability.
There is also the temptation to genetically edit entire animal species —
malaria-causing mosquitoes in Burkina Faso or mice hosting ticks that carry
Lyme disease in the US.
The researchers in charge of those projects are advancing carefully,
however, fully aware of the unpredictability of chain reactions on the
ecosystem.
Charpentier doesn’t believe in the more dystopian scenarios predicted for
gene therapy, including American “biohackers” injecting themselves with
Crispr technology bought online.
“Not everyone is a biologist or scientist,” she said.
And the possibility of military hijacking to create soldier-killing
viruses or bacteria that would ravage enemies’ crops?
Charpentier thinks that technology generally tends to be used for the
better.
“I’m a bacteriologist — we’ve been talking about bioterrorism for years,”
she said. “Nothing has ever happened.”
BSS/AFP/FI/1043 hrs