New Age of Genome Editing May Lead to a Cure for Sickle Cell Anemia

A new age of genome editing could lead to a cure for sickle cell anemia. Scientists have shown that changing a single letter of the DNA of human red blood cells in the laboratory increases their production of oxygen-carrying hemoglobin, which could be huge for treating sickle cell anemia.

The new genome editing technique works by introducing a beneficial, naturally-occurring genetic mutation into cells. The researchers switch on a sleeping gene that's active in the womb but turned off in most people after birth.

"An exciting new age of genome editing is beginning, now that single genes within our vast genome can be precisely cut and repaired," said Merlin Crossley, the leader of the new study, in a news release. "Our laboratory study provides a proof of concept that changing just one letter of DNA in a gene could alleviate the symptoms of sickle cell anemia and thalassemia-inherited diseases in which people have damaged hemoglobin."

People produce two different types of hemoglobin, which is the molecule that picks up oxygen in the lungs and transports it around the body. During development in the womb, the fetal hemoglobin is switched on, which has a high affinity for oxygen. After birth, though, this gene is shut off and the adult hemoglobin gene is switched on-except for those who have damaged hemoglobin genes.

In this case, the researchers introduced a single-letter mutation into human red blood cells using genome-editing proteins known as TALENS, which can be designed to cut a gene at a specific point, as well as providing the desired piece of donor DNA for insertion.

"Breaks in DNA can be lethal to cells, so they have in-built machinery to repair any nicks as soon as possible, by grabbing any spare DNA that seems to match-much like you might darn a red sock with any spare red wool lying around," said Crossley. "We exploited this effect. When our genome editing protein cuts the DNA, the cell quickly replaces it with the donor DNa that we have also provided."

The findings are published in the journal Nature Communications.

For more great science stories and general news, please visit our sister site, Headlines and Global News (HNGN).