In a world first, precise “chemical surgery” has been performed on human embryos to remove disease.

Chinese researchers from Sun Yat-sen University told the BBC, that they used a technique called base editing to correct a single error out of the three billion “letters” of our genetic code.

Base editing alters the fundamental building blocks of DNA, which are commonly known by their respective letters.

All the instructions for building and human body are encapsulated in these combinations. 

They altered lab-made embryos, which were not implanted, to remove the disease beta-thalassemia. The potentially life-threatening blood disorder is caused by a change to a single base in the genetic code, known as a point mutation.

The team in China editing it back, as well as scanned DNA for the error and then converted it a G to an A, correcting the fault.

The study is thought to open up new avenues for treating patients and preventing babies being born with beta-thalassemia, in addition to other inherited diseases.

The experiments were carried out in tissues taken from a patient with the blood disorder and in human embryos made through cloning.