Rob Stein

The powerful gene-editing technique known as CRISPR has raised a lot of hope in recent years for its potential to offer new ways to treat many diseases, including cancer. But until now, scientists have released very little information about results of tests in patients.

On Wednesday, researchers revealed data from the first study involving U.S. cancer patients who received cells genetically modified with CRISPR.

Scientists have created a new way to edit DNA that appears to make it even easier to precisely and safely re-write genes.

The new technique, called prime editing, is designed to overcome some of the limitations of CRISPR. That technique, often described as a kind of molecular scissors for genes, has been revolutionizing scientific research by letting scientists alter DNA.

Victoria Gray slides open a closet door, pulls out a suitcase and starts packing piles of clothes.

"My goodness," says Gray. "Did I really bring all this?"

Gray, who has sickle cell disease, is the first patient with a genetic disorder whom doctors in the United States have tried to treat using the powerful gene-editing technique CRISPR.

There's been a lot of excitement lately that the powerful gene-editing technique CRISPR could offer a new way to treat health problems ranging from cancer to blindness.

But there hasn't been much direct scientific evidence in actual patients about whether it might work or would be safe — until now.

Chinese scientists have published the first report in a scientific journal of an attempt to use CRISPR-edited cells in a patient--a 27-year-old man who is HIV-positive.

Scientists have invented a device that can quickly produce large numbers of living entities that resemble very primitive human embryos.

Researchers welcomed the development, described Wednesday in the journal Nature, as an important advance for studying the earliest days of human embryonic development. But it also raises questions about where to draw the line in manufacturing "synthetic" human life.

First it was human embryos. Now scientists are trying to develop another way to modify human DNA that can be passed on to future generations, NPR has learned.

Reproductive biologists at Weill Cornell Medicine in New York City are attempting to use the powerful gene-editing technique called CRISPR to alter genes in human sperm. NPR got exclusive access to watch the controversial experiments underway.

Updated at 4:05 p.m. ET

For the first time, doctors in the U.S. have used the powerful gene-editing technique CRISPR to try to treat a patient with a genetic disorder.

Scientists have created living entities that resemble very primitive human embryos, the most advanced example of these structures yet created in a lab.

The researchers hope these creations, made from human embryonic stem cells, will provide crucial new insights into human development and lead to new ways to treat infertility and prevent miscarriages, birth defects and many diseases. The researchers say this is the first time scientists have created living models of human embryos with three-dimensional structures.

A Russian scientist says he wants to create more genetically modified babies, flouting international objections that such a step would be premature, unethical and irresponsible.

Denis Rebrikov, a molecular biologist who heads a gene-editing lab at the Kulakov National Medical Research Center for Obstetrics, Gynecology and Perinatology in Moscow, claims he has developed a safe — and therefore acceptable — way to create gene-edited babies.