Genome editing breakthrough used to treat haemophilia

Scientists have achieved a medical breakthrough by utilising a new gene therapy technique to correct haemophilia in animal test subjects.

A collaboration between the Children's Hospital of Philadelphia and Sangamo BioSciences has found a way of using genetically engineered enzymes called zinc finger nucleases (ZFNs) as a means of conducting genome editing procedures.

Through this method, researchers were able to target the precise location of mutated DNA in living mice and repair the defect that causes the blood disease.

It represents the first time that this technique has been performed on a living animal and achieved clinically meaningful results, with improvements persisting for the entire eight-month duration of the study without toxic effects.

Study leader Dr Katherine High, a haematologist and gene therapy expert, said: "We need to perform further studies to translate this finding into safe, effective treatments for haemophilia and other single-gene diseases in humans, but this is a promising strategy for gene therapy."

According to NHS data, the most common haemophilia variety, type A, affects one in every 5,000 males born and can be extremely detrimental, as it inhibits the ability of blood to clot.