Rewrite the rules of life
In June, on an unusually windy day, Kevin Esvelt climbed aboard the hyannis boat on his way to Nantucket. An assistant professor of bioengineering at the Massachusetts institute of technology is introducing one of the island’s most intractable problems: lyme disease. He spent most of his time at work and his fatigue showed up. The buttons on his grey needle-shaped shirt were not aligned, and the rings around his dark blue eyes made him look like a couch raccoon.
Esvette, 34, who directs the MIT sculpture evolution team, is trying to design molecular tools that can radically change the natural world. If the residents of Nantucket agree, Esvelt intends to use these tools to rewrite the DNA of white-footed mice to make them immune to the bacteria that cause lyme disease and other ticks. He and his team will breed mice in the laboratory and then conduct a preliminary experiment, placing them on an uninhabited island. If the number of infected ticks begins to decline, he will seek approval to repeat the process in Nantucket and nearby Martha’s vineyard.
More than a quarter of Nantucket residents are infected with lyme disease, one of the fastest spreading diseases in the United States. The disease is usually accompanied by a rash of red bull eyes with fever and chills. When the disease is detected early, most cases can be cured by a course of antibiotics. For many, however, pain and neurological symptoms can last for years. Fear of lice has changed the nature of summer in communities across the northeast – few parents now allow their children to walk barefoot through the grass or gently into the woods.
“What if we can keep it going and make it go away?” Esvette asked more than two dozen officials and members of the public who had gathered on the island. He explained that white-footed mice are the primary repository for lyme disease, which is transmitted to humans by ticks. “It’s an ecological problem,” Mr. Eastwood said. We hope to develop an ecological solution to break the tick transmission cycle in the environment where these pathogens infect. ”
The lyme vaccine has not yet been approved for use in humans, but there is a dog used to treat mice. Esvelt and his team will begin vaccinating mice to sequence the DNA of the most protective antibodies. They then implanted the genes needed to make the antibodies into the eggs of the mice. The mice were naturally immune to liam. Eventually, if enough of these species are released to mate with wild mice, the entire population will become resistant. As with criticism, antibodies in mice kill any tick that bites them. No infected ticks, no infected people. “Get the mice,” esvette told me. “The entire transmission cycle has been broken.”
In the past year, Esvelt had dozens of lime, not only in Nantucket and Martha’s vineyard, BBS, and all over the world from Chile’s synthetic biology seminar to Pittsburgh, President barack Obama’s White House boundary. When he appeared, esvette told the audience that he wanted his two children — he had a three-year-old son and almost a daughter — to grow up in the world. But this is not a real conference on infectious diseases, the insect society negotiations and the international symposium on conservation. He has begun what he thinks is a more important task.
Esvelt and his colleagues first described crispr in 2014, a revolutionary gene editing tool that combines so-called gene-driven natural phenomena to change the genetic fate of species. Genes drive work by overcoming traditional Mendelian genetic rules. Typically, any offspring of sexual organs will receive half of the genome from each parent. But since the 1940s biologists have realised that some genetic factors are “selfish” : evolution has given them more than 50 per cent of their genetic opportunities. This feature can propagate certain functions at an unusual rate.
Before crispr, biologists lacked the tools to force certain genetic changes in a population. But the system is essentially a molecular scalpel that can alter or remove any sequence of billions of nucleotides in the genome. By placing it in an organism’s DNA, scientists can ensure that new genes are replicated in each generation. For example, the parasite mutations that prevent malaria can be designed to be mosquitoes and spread when they regenerate. Each generation will have more offspring, until sometimes the entire species will have it.
There have never been more powerful biological tools, or more likely to improve the world and endanger it. Esvelt hopes to use this technology as a lever to start what he believes is often hidden and unnecessary duplication of scientific research. “The only way to do an experiment that can kill an entire species is to be completely transparent,” he told me. “If all studies are public, genetic factors are most likely to succeed for moral and practical reasons. If we can do that for gene drive, we can do that for other science. “