dryriver writes: Chinese researchers have taken tissue from a beta-thallasemia patient, created cloned embryos from that patient's cells, and used a genetic editing technique known as Base Editing to correct the gene mutation that causes beta-thallasemia. The embryos were not implanted in a womb, so no actual babies were created during the procedure. The BBC reports: "Precise 'chemical surgery' has been performed on human embryos to remove disease in a world first, Chinese researchers have told the BBC. The team at Sun Yat-sen University used a technique called base editing to correct a single error out of the three billion 'letters' of our genetic code. They altered lab-made embryos to remove the disease beta-thalassemia. The embryos were not implanted. The team says the approach may one day treat a range of inherited diseases. Base editing alters the fundamental building blocks of DNA: the four bases adenine, cytosine, guanine and thymine. Base editing works on the DNA bases themselves to convert one into another. Prof David Liu, who pioneered base editing at Harvard University, describes the approach as 'chemical surgery.' He says the technique is more efficient and has fewer unwanted side-effects than Crispr. He told the BBC: 'About two-thirds of known human genetic variants associated with disease are point mutations. So base editing has the potential to directly correct, or reproduce for research purposes, many pathogenic [mutations].'"