Excitement brews around promise of gene editing

Matthew Porteus, MD, PhD. Photo credit: Timothy Archibald

For 15-year-old David Sanchez of Redwood City, California, Lucile Packard Children’s Hospital Stanford is truly his second home. He has come here more times than he can count since as far back as he can remember. David has sickle-cell disease, an inherited disorder caused by a genetic mutation. He visits Packard Children’s for weekly blood tests and monthly apheresis treatments, a three-hour transfusion in which his diseased red blood cells are replaced with donor cells. David’s story was recently featured in Stanford Medicine Magazine in an article about promising gene-editing research taking place at Stanford that could hold the key to fixing genetic mutations like the one that causes sickle-cell disease.

Read more – Target, delete, repair: CRISPR is a revolutionary gene-editing tool, but it’s not without risk

David Sanchez with Grandmother Dolores Sanchez. Photo credit: Timothy Archibald

This gene-editing research is centered on a technology called CRISPR, which has already been well publicized in the scientific community and mainstream media, where it has generated excitement, cautious optimism and many questions. The technology is allowing researchers to target specific genes and replace them with others. Let that sink in for moment, and you can understand why this technology is not without controversy. There’s been energized discussion around the ethics of gene editing and the potential dangers for its misuse. But for patients like David who suffer from extremely painful complications of sickle-cell disease, the hope for a potential solution is the highest priority.

Matthew Porteus, MD, PhD, hematologist and associate professor of pediatrics in stem cell transplantation, is leading clinical research for CRISPR at Stanford and hopes to launch Stanford’s first clinical trial of CRISPR. Currently his lab is working to prove that the technology is safe for testing in people.

Dr. Porteus likens the genetic mutation that occurs in sickle-cell disease to a “typo in a book containing 6 billion letters.” The goal of his trial is to “correct the genetic typos that cause sickle-cell disease so that patients like David can live long, healthy lives.”

Patients with sickle-cell disease have two defective genes that cause their red blood cells to become stiff and sticky. The Stanford Medicine article explains that, “In his trial, Porteus plans to repair and replace defective blood stem cells in patients with sickle-cell disease.”

“The repaired stem cells could create enough normal red blood cells for the patient to be symptom-free for life,” Porteus says in the article. “That’s the ultimate goal.”

If the trial is successful, those monthly infusions of donor red blood cells could be a thing of the past for patients like David.