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From VOA Learning English, this is the Health Report.
American scientists have, for the first time, taken stem cells from human embryos that are genetic copies of living people. The goal is to create better treatments for disease. But the work has raised ethical concerns about cloning, or making genetic copies, of people. It is illegal to clone a human being in more than 12 states. Some medical researchers are carrying out what is called therapeutic cloning to try to fight disease. Still, even that method is banned in seven states. One state where therapeutic cloning is not banned is Oregon. Researchers at Oregon Health and Science University in Portland were able to put human DNA into modified human eggs. They produced embryos that were genetically the same as the people who had donated their DNA.
The researchers then took stem cells from the embryos. These cells are called “master cells.” Scientists know how to use chemicals to cause master cells to develop into any tissue in the body. The idea is that doctors could use tissue created this way to replace diseased organs. The new body tissue would be a genetic match of the person receiving it. And there would be no danger that the patient’s body would reject the new tissue. That can happen with normal transplants. Shoukhrat Mitalipov led the study, which involved more than 20 researchers. The scientists believe the stem cells could give doctors a new way to treat Parkinson’s disease, a degenerative movement disorder. Scientists believe they could use the DNA from a skin cell of someone with Parkinson’s disease to create a personalized treatment.