Using a technique called “base editing,” Chinese scientists have altered the DNA of controversial lab-grown embryos to cure a deadly blood disease.
Potentially, doctors claim, editing an embryo’s gene sequence can cure a sometimes fatal, and debilitating life-long blood disease called beta thalassemia. British scientific journal Protein and Cell published the findings.
Sufferers of beta thalassemia inherit the disorder from their parents. Every person on the planet has a one in three hundred chance of inheriting the faulty genes. However, within Mediterranean, Middle Eastern and Asian genetic groups, the statistics rise to one in thirty.
People born with the condition either don’t produce enough of, or they produce too much hemoglobin. Consequently, regular iron supplements are not only ineffective but dangerous.
Currently, the only treatment for individuals with beta-thalassemia has been an extremely risky bone marrow or stem cell transplant. Additionally, many patients undergo blood transfusions on a regular basis. Furthermore, chelation therapy is the only medication they can take to seek to prevent any build-up of an excess of iron, which can be deadly.
Usually, those with extreme forms of the disease have abnormal facial features and experience extreme lethargy. As young children, they are pale and sickly.
Researchers at the Sun Yat-sen University claim to have “rewritten” DNA within the embryos. Essentially, when scientists remove the faulty proverbial microscopic message within the DNA, and replace it with the correct message, beta thalassemia, also known as Mediterranean anemia, they can genetically eliminate it.
Professor Robin Lovell-Badge, of London’s Francis Crick Institute in London, called this “An ingenious step forward.”
Indeed, many scientists in the field of genetics feel that they could potentially eradicate many other hereditary diseases in the same way. However, Lovell-Badge did go on to add “in many countries, including China, there needs to be more robust mechanisms established for regulation, oversight, and long-term follow-up.”
Next, Liu and his team utilized genetic correction techniques similar to Crispr, taking the already revolutionary method a step further. In fact, Liu claims that his technique is not only more effective, but it also has fewer side-effects.
DNA is composed of four nucleobases called thymine (T), cytosine (C), adenine (A), and guanine (G). The entire human body is built from encoded combinations of each of these building blocks. Once Liu and his team scanned the DNA and located the error, they converted the guanine to adenine.
Nevertheless, the ability to start using the technique in therapeutic patient settings is still a long way off. Also, ethical issues regarding the way the scientists conducted the research, and what this could mean for so-called “designer babies” will no doubt enter an arena of fierce public debate.
After all, most nations deem medical testing on embryos, as the Chinese have undertaken in this instance, to be illegal. The scientists destroyed the embryos once they concluded the research.
Furthermore, none of the Chinese scientists demonstrated the research to be successful in a living human.