Could the solution for sickle cell disease lie with gene editing? New research, not yet in humans, suggests that a novel gene-editing strategy holds promise for people with this and other serious inborn disorders of hemoglobin, the oxygen-carrying molecules in red blood cells.

The results are so promising that the study team at Fred Hutchinson Cancer Research Center hopes that gene editing could even prove to be a cure, they said. The term “gene editing” refers to technologies that can be used to make precise modifications to the genome.

The ongoing research is led by Dr. Olivier Humbert, a staff scientist in the lab of Dr. Hans-Peter Kiem at Fred Hutch. The team used a novel gene-editing approach to increase blood stem cells’ production of the type of hemoglobin that is found in high levels in fetuses and infants. This is important because having more fetal hemoglobin in red blood cells can compensate for the dangerous problems associated with the defective or missing form of adult hemoglobin that is a hallmark of the inborn hemoglobin disorders collectively called hemoglobinopathies: sickle cell disease and beta thalassemias.

About 300,000 children worldwide are born each year with sickle cell disease, the most well-known hemoglobin disorder, and sickle cell is a leading cause of child death in many African nations. This genetic disorder causes people’s red blood cells to deform, a change that leads to episodes of excruciating pain, stroke, and organ failure. The only cure currently available is bone marrow transplant, which is out of reach of many patients and associated with significant side effects.

Humbert presented the team’s findings last Friday during the annual meeting of the American Society of Gene & Cell Therapy. His talk was one of just four of the meeting’s nearly 1,000 research abstracts to be featured in the Presidential Symposium, the conference’s most prominent venue.

Working with an advanced laboratory model, Humbert and colleagues used the gene-editing strategy known as CRISPR to remove cells’ normal genetic mechanism for turning down the production of fetal hemoglobin. In his talk, Humbert showed that the team’s approach efficiently made the key genetic tweak, and that high percentages of the modified cells survived over time in the bone marrow and blood.

Most thrilling to the researchers was the evidence they found that the procedure might prove to help people with hemoglobinopathies. “Most importantly, when we measured fetal hemoglobin levels, it was in the therapeutic range,” Humbert said.

“These levels, we hope, would be curative”—an exciting prospect for the team, added Kiem, who holds the Endowed Chair for Cell and Gene Therapy at Fred Hutch.