Tiny vials of recently repaired blood cells are thriving in a Stanford incubator, proof that a powerful new gene-editing technique is fixing errant genes that cause so much human suffering.
Until recently, gene therapy was laborious, crude and unsafe for human testing. But the new technology, called CRISPR-Cas9, acts as a microscopic scalpel, performing genomic surgery with a precision, efficiency and affordability once thought unimaginable.
The research being done at the Stanford School of Medicine, led by Dr. Matthew Porteus, is part of an accelerating research movement made possible using the new technique to try to cure genetic diseases such as sickle cell anemia and muscular dystrophy. These labs are steadily advancing through cell-based and animal trials, as fledgling biotech companies raise large sums of money needed to bring the therapies to market.
“Now, with lots of people — hundreds or thousands of labs — working with CRISPR, this means the possibility of actually finding a way to cure patients of disease increases dramatically,” said Porteus, an associate professor of pediatrics and a pioneer in gene editing.
Using the campus’s first-ever cell manufacturing plant, to be completed this spring, the Stanford team aims to start human trials in 2018. The researchers are targeting two severe blood diseases — sickle cell anemia and beta thalassemia — and several diseases that ravage the immune system.
Meanwhile, scientists at Duke University and two other independent labs on Friday announced that they are using the same approach to fix a muscle gene, restoring function in mice with an incurable type of muscular dystrophy. Their findings were published in the journal Science.
Boston researchers are deploying the tool to treat a rare inherited eye disease that can cause blindness. Other teams are working to fix the genes that cause Huntington’s disease, Sanfilippo syndrome and cystic fibrosis.
But its therapeutic promise is what excites the medical community, especially as the price of the new technology plunges and access expands.
It has buoyed hopes in the beleaguered field of gene therapy, dealt a major setback in 1999 when Jesse Gelsinger, an Arizona teenager with a genetic liver disease, had a fatal reaction to the virus that scientists had used to insert a corrective gene.
These older approaches could not guarantee that the new gene was spliced into the right place. It also risked disruption of adjacent genes.
While there have been recent improvements with two more precise techniques, they are time-consuming and tricky.
CRISPR — which stands for “clustered regularly interspaced short palindromic repeats,” or clusters of brief DNA sequences that read similarly forward and backward — is the game-changer. Only 3 years old, it works like the search-and-replace function of a computer.
CRISPR has been in the crosshairs of controversy because of its profound potential to rearrange the basic building blocks of life. In December, experts gathered in Washington, D.C., to urge limits to its use in creating dangerous new organisms or “designer babies.”
From the article on Mercury News: “The scientists plan to harvest some of the sick cells that give rise to the blood or immune system cells, called stem cells, from the bone marrow of a patient. Then the patient would undergo intensive chemotherapy to kill the remaining sick stem cells and make room for new ones.” What could go wrong?