Recently, scientists have been using chemical “scissors” to edit, or change, the DNA in living organisms. This swapping out of parts of DNA could replace faulty genes.
In theory, it also might make it possible to create designer babies that are smarter or better-looking than other individuals. But some people have questioned whether such tinkering with human cells would be like playing god. Many people also worry that editing isn’t safe.
Those and other concerns have led some people to wonder if gene editing is so unethical that it should be banned. To answer that, a host of experts met in Washington, D.C., this week. After reviewing the science and other issues, they offered a temporary green light. On December 3, they said that research on human gene editing is needed and so should proceed.
But the experts also gave one big exception. Any cells edited in a lab may not be used to establish a pregnancy, they said. In other words, no designer babies! That also would mean researchers could not fix genetic diseases before a baby was born.
In recent years, scientists have devised increasingly precise chemical tools for cutting and pasting DNA. One recent result: Scientists created beagles with extra muscle. In that case, the researchers used “scissors” known as CRISPR/Cas9.
Such gene-editing tools have become so cheap and easy to use that it might be possible to use them soon to cure genetic diseases. But some people think the technology also could be misused, either accidently or on purpose.
The recommendations made at the end of this week’s summit came from a 12-person committee. It had organized the meeting. These experts made it clear that any concerns they have are mostly about editing genes that would be passed on to future generations. This type of editing is called germline editing.
‘Somatic’ editing? No problem
Those experts had no problem with a different type of editing, known as somatic cell editing. Somatic cells are all of those making up the body except the germ cells. Those are the egg and sperm cells that carry on genetic information to the next generation. Germ cells also include cells that will become eggs or sperm and fertilized eggs or embryos made from combining eggs and sperm.
Trials are already underway to edit somatic cells of people. So far, all editing has taken place outside the body. Altered cells are then used to treat a patient.
[media-credit name=”SHARON LEESE/GOSH” align=”alignnone” width=”350”][/media-credit] A cancer in this child, known as Baby Layla, was put into remission by a human gene-editing procedure.
One notable success: Doctors announced on November 5 that gene editing helped push a 1-year-old girl’s leukemia (a blood cancer) into remission. The baby, named Layla, was treated with edited immune cells. In her case, the editing “scissors” used to slice genes are known as TALENs. They are actually enzymes that researchers engineer to latch on to DNA at specific sites and then cut it. This marked the first time TALENs have been successfully used to treat a human, said doctors at Great Ormond Street Hospital in London, England.Earlier this week, a company called Sangamo BioSciences announced that human trials could begin next year using gene editing to replace a broken gene in hemophiliacs (HE-moh-FEE-lee-aks). These people have inherited an inability to make their blood clot. As such, even a simple cut could cause a life-threatening loss of blood without immediate medical treatment. In the trial, researchers would use a different type of molecular scissors called zinc finger nucleases. If those trials go ahead, it will be first the time gene editing takes place inside someone’s body.
The summit’s organizing committee said this week that such research on somatic cells could continue. It approved such research because it only affects one person. Changes made in that person, such as fixing a broken gene, could not be passed on to his or her children and grandchildren. Even those studies must, however, abide by existing rules for gene therapies.