At a recent medical convention, researchers presented their findings using CRISPR gene editing to treat Angelman syndrome in mice. Scientists from Neuroscience Center at the University of North Carolina at Chapel Hill injected the controversial enzyme into the brains of embryonic mice.
CRISPR successfully corrected the genetic mutation that causes the syndrome.
The Chapel Hill clinicians also found they were able to replicate their experiment using human neural tissue. With further study, the research group believes they can develop a revolutionary treatment for the debilitating genetic condition. Notably, if the technique proves successful, it could be adapted for use with similar ailments like autism spectrum disorder.
The Angelman Syndrome Treatment
According to the U.S. National Library of Medicine, Angelman syndrome is a genetic condition that afflicts the nervous system. The disorder’s most common symptoms are delayed development, intellectual disability, seizures, and impaired movement and balance.
Medical researchers have found the syndrome is caused by a mutation or absence of a paternal gene called UBE3A.
Currently, there is no cure for Angelman syndrome. Sufferers can treat their condition with anticonvulsant medication and cognitive and physical therapy.
The Chapel Hill team injected a CRISPR-enhanced virus into the brains of 10 embryonic UBE3A-lacking mice days before they were born. Subsequently, scientists tested the mice five months after treatment and none had the Angelman mutation.
Mark Zylka, director of the university neuroscience group, has high hopes for his organization’s new treatment. “The earlier you put the genes back and try to fix the problem, the better the therapeutic benefit will be.”
Zylka also predicted doctors will use CRISPR to prevent Angelman syndrome in humans within 4 years.
Possible Risk Factors
Despite the promising nature of the Chapel Hill research team’s findings, other scientists have expressed concerns about prenatal gene editing.
Fred Hutchinson Cancer Research Center associate Antonio Bedalov told Spectrum that altering human fetal brain tissue is problematic because its long-term implications are unknown. Similarly, University of California, Davis professor David Segal argued CRISPR research hasn’t reached a point where it can be safely used in human embryos
“The idea that you could treat a fetus with [an enzyme] is just a very uncharted area, and there could contain a lot of risks,” said Segal.
University of Texas at San Antonio associate neuroscience professor Hye Young Lee warned using a viral agent to correct Angelman syndrome is potentially unsafe. Dr. Lee explained the CRISPR delivery system could introduce new rogue mutations into a prenatal brain.
The Autism Connection
Researchers still need to thoroughly study the university team’s gene editing treatment, but its application as an autism therapy is intriguing. Though not directly related, studies have found autism and Angelman syndrome often manifest in the same patients. In fact, a 2018 study found the two disorders may be caused by similar parental genetic defects.
Consequently, if scientists can identify and correct the specific gene responsible for causing autism, prenatal treatments may prevent its onset.
Unfortunately, federal authorities won’t authorize the new technique use as preventative medicine anytime soon. For one thing, human CRISPR trials were only authorized in the U.S. in January. Even then, the use of the enzyme is still extraordinarily controversial in the international medical community because it’s so new.