They also hold the promise of
correcting gene mutations in patients, whether in blood cells, muscle cells, or tumor cells.
The Porteus team started with human stem cells from the blood of patients with sickle cell disease,
corrected the gene mutation using CRISPR and then concentrated the human stem cells so that 90 percent carried the corrected sickle cell gene.
Last month, researchers from the Netherland's Utrecht institute reported in Cell Stem Cell that CRISPR
corrected the gene mutation responsible for cystic fibrosis in stem cells developed from two children with the life - threatening disease.
We can even manipulate the genome directly with new editing techniques to examine, create, or
correct gene mutations that are specific to one person.
Not exact matches
And Crispr - Cas9 isn't even the only type of Crispr out there: On April 12, researchers at the University of Texas Southwestern Medical Center announced they had successfully paired the
gene - editing tool with a different kind of enzyme, called Cpf1, to
correct mutations associated with the devastating muscle - wasting disorder Duchenne muscular dystrophy.
The researchers
corrected a
mutation in liver cells in mice by snipping out the
gene and sewing in a healthy copy of it.
Researchers from Duke University had previously used CRISPR to
correct genetic
mutations in cultured cells from Duchenne patients, and other labs had
corrected genes in single - cell embryos in a laboratory environment.
The researchers determined that CRISPR had successfully
corrected a
gene that causes blindness, but Kellie Schaefer, a PhD student in the lab of Vinit Mahajan, MD, PhD, associate professor of ophthalmology at Stanford University, and co-author of the study, found that the genomes of two independent
gene therapy recipients had sustained more than 1,500 single - nucleotide
mutations and more than 100 larger deletions and insertions.
As Saaïd Safieddine, CNRS Director of Research at the Institut Pasteur and co-senior author of the study with Prof. Christine Petit (head of the Genetics & physiology hearing unit at the Institut Pasteur), explains, «we have just shown that it is possible to partially
correct a specific form of hereditary hearing loss accompanied by balance problems using local
gene therapy performed after the embryogenesis of the ear, which is primarily affected by the
mutation responsible for the disorder.
«By either skipping a
mutation region or precisely repairing a
mutation in the
gene, CRISPR - Cpf1 - mediated genome editing not only
corrects Duchenne muscular dystrophy
mutations but also improves muscle contractility and strength,» said co-author Dr. Rhonda Bassel - Duby, Professor of Molecular Biology and Associate Director of the Hamon Center for Regenerative Science and Medicine.
«This work demonstrates the feasibility of using a single
gene editing platform, plus the regenerative power of stem cells to
correct genetic
mutations and restore dystrophin production for 60 percent of Duchenne patients,» said Pyle, associate professor of microbiology, immunology and molecular genetics and member of the Broad Stem Cell Research Center.
For his part, Collins, who has led NIH since 2009 and been kept on by the Trump administration, pointed to an array of promising NIH activities, including the development of new technologies to provide insights into human brain circuitry and function through the Brain Research through Advancing Innovative Neuroethologies (BRAIN initiative) and the use of the
gene - editing tool CRISPR - Cas9 to
correct mutations and clear the way to develop and test a «curative therapy» for the first molecular disease: sickle cell disease.
UT Southwestern Medical Center researchers successfully used a new
gene editing method to
correct a
mutation that leads to Duchenne muscular dystrophy (DMD) in a mouse model of the condition.
In an independent effort, they introduced progressively smaller pieces of DNA from the large region known to contain the
gene into embryos of the mutant mice, looking for the smallest piece that would
correct the
mutation in adult mice and restore a normal rhythm.
Still, the standard form of liver - targeted
gene therapy carries a range of potential complications, including the risk of harmful
mutations and of the body mounting an immune response against the viral vectors used to carry the
correct forms of the defective
genes responsible for haemophilia.
A Yale - led research team used a new
gene editing strategy to
correct mutations that cause thalassemia, a form of anemia.
Yale researchers successfully
corrected the most common
mutation in the
gene that causes cystic fibrosis, a lethal genetic disorder.
«
Gene editing used to
correct mutation in cystic fibrosis.»
It also opens up possible new treatment approaches for other diseases that have thus far required more intrusive methods to
correct single -
gene mutations.
The research, the cover story of this month's Science Advances, builds upon previous studies from Dr. Olson in which CRISPR - Cas9
corrected a single
gene mutation that caused DMD in mice.
Scientists have developed a CRISPR
gene - editing technique that can potentially
correct a majority of the 3,000
mutations that cause Duchenne muscular dystrophy (DMD) by making a single cut at strategic points along the patient's DNA, according to a study from UT Southwestern Medical Center.
Since people with a mutant copy of the MYBPC3
gene have a 50 percent chance of passing it on to their own children, being able to
correct the
mutation in embryos would prevent the disease not only in affected children, but also in their descendants.
And while scientists have had some success in switching off
genes by inserting or deleting random sequences, they have not yet been able to use CRISPR / Cas9 to paste in (or «knock in») specific new sequences to
correct mutations in T cells.
First, the researchers took skin cells from patients and introduced
genes to
correct the defective
mutations.
He and others have recently used
gene - editing tools to
correct mutations in human iPS cells but haven't used the same combination of methods or done the same set of experiments to determine whether the iPS - derived cells are safe.
Next, they used a virus to insert a
gene into the cells that
corrects the
mutation in the dystrophin
gene.
NMD also ensures that many
mutations in our
genes do not cause any disease symptoms — as long as the second copy of the
gene affected is still intact and thus a
correct version of the body plan is available.
Exciting clinical applications of
gene editing include
correcting the
mutation in the bone marrow stem cells of patients with sickle cell disease or hemophilia.
While effective, the downside to these approaches to vision rescue is that each disease requires its own form of
gene therapy to
correct the particular genetic
mutation involved, a time consuming and complex process.
They think this
gene hub could be targeted with drugs to
correct some of the damage caused by GATA4
mutations.
To
correct RPE65
mutation damage, scientists are evaluating drugs, cell transplants and
gene delivery in Rpe65 knockout, transgenic and spontaneous mutant mice, and spontaneous Rpe65 - mutant dogs.
If
mutations in
genes can not be
corrected efficiently, they have the potential to accumulate and cause cancer.
«If a patient has a
mutation in a specific
gene, it would be a way of giving them a normal copy to try to
correct that
gene.
Instead, we can target other
genes that impact the same protein or biological process and
correct the
mutation upstream or downstream in the network,» explained Krogan.
Also, about 500 other disease - causing
mutations have been identified in the HBB
gene, so
correcting the
gene could potentially cure a multitude of HBB - related diseases worldwide.
One of the groups hoping to exploit our understanding of the HBB
gene is CRISPR Therapeutics, which wants to use the
gene editing technique CRISPR to permanently
correct the
mutation.
The technique is also inefficient,
correcting only a small percentage of
gene mutations, and transplantation success has proven rare in clinical trials testing
gene therapy to treat beta thalassemia.
Over time, the repair system in the cell works worse, and much of this damage either is not
corrected at all, disrupting the expression of
genes, or converted into
mutations.
Production of
Gene -
Corrected Adult Beta Globin Protein in Human Erythrocytes Differentiated from Patient iPSCs After Genome Editing of the Sickle Point
Mutation.
Could a new CRISPR
gene - editing technique
correct a majority of the 3,000
mutations that cause Duchenne muscular dystrophy?
Scientists achieve first safe repair of single -
gene mutation in human embryos Scientists have, for the first time,
corrected a disease - causing
mutation in early stage human embryos with
gene... Read more
Second, the cells need to undergo a sophisticated
gene editing process to
correct the disease - causing
mutation.
Review of «Production of
gene -
corrected adult beta globin protein in human erythrocytes differentiated from patient iPSCs after genome editing of the sickle point
mutation» from Stem Cells by Stuart P. Atkinson