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Although not ready yet, powerful gene editing tools may one day be used on human embryos, eggs and sperm to remove genes that cause inherited diseases, according to a report by U.S. scientists and ethicists released on Tuesday.

The report from the National Academy of Sciences (NAS) and the National Academy of Medicine said scientific advances make gene editing in human reproductive cells “a realistic possibility that deserves serious consideration.”

The statement signals a softening in approach over the use of the technology known as CRISPR-Cas9, which has opened up new frontiers in genetic medicine because of its ability to modify genes quickly and efficiently.

In December 2015, scientists and ethicists at an international meeting held at the NAS in Washington said it would be “irresponsible” to use gene editing technology in human embryos for therapeutic purposes, such as to correct genetic diseases, until safety and efficacy issues are resolved.

The latest NAS report now says clinical trials for genome editing of the human germline could be permitted, “but only for serious conditions under stringent oversight.”

CRISPR-Cas9 works as a type of molecular scissors that can selectively trim away unwanted parts of the genome, and replace it with new stretches of DNA.

Genome editing is already being planned for use in clinical trials of people to correct diseases caused by a single gene mutation, such as sickle cell disease. But these therapies affect only the patient.

The concern is over the use of the technology in human reproductive cells or early embryos because the changes would be passed along to offspring.

Research using the powerful technique is plowing ahead even as researchers from the University of California and the Broad Institute battle for control over the CRISPR patent.

Although gene editing of human reproductive cells to correct inherited diseases “must be approached with caution, caution does not mean prohibition,” the committee said in a statement.
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Researchers say they may have found a way to stave off aging. They say you might need to eat less.

Writing in the journal Molecular & Cellular Proteomics, researchers from Brigham Young University say eating less can slow the aging of cells in the body.

Fewer calories slow down a mechanism in the cells called ribosomes, at least in mice. They are responsible for making vital proteins in the cells, but with fewer calories they slow down, giving them more time to repair themselves, researchers said.

Ribosomes, researchers say, use from 10 to 20 percent of the cell’s energy to make those proteins.

“Because of this, it’s impractical to destroy an entire ribosome when it starts to malfunction,” said a news release about the study. “But repairing individual parts of the ribosome on a regular basis enables ribosomes to continue producing high quality proteins for longer than they would otherwise. This top quality production in turn keeps cells and the entire body functioning well.”

John Price, a biochemistry professor at Brigham Young and the senior author of the study, likens ribosomes to cars.

“The ribosome is a very complex machine, sort of like your car, and it periodically needs maintenance to replace the parts that wear out the fastest,” he said. “When tires wear out, you don’t throw the whole car away and buy new ones. It’s cheaper to replace the tires.”

To reach their conclusions, researchers looked at two groups of mice. One group was able to eat as much as it wanted, while the other group was put on a diet with 35 percent fewer calories.

“When you restrict calorie consumption, there’s almost a linear increase in lifespan,” Price said. “We inferred that the restriction caused real biochemical changes that slowed down the rate of aging.”

While previous studies have suggested a link between lower calories and slowed aging, this is first to show how the ribosomes can influence aging.

“The calorie-restricted mice are more energetic and suffered fewer diseases,” Price said. “And it’s not just that they’re living longer, but because they’re better at maintaining their bodies, they’re younger for longer as well.”

Despite the findings, Price says calorie restriction as an anti-aging strategy has not been tested in humans. He did add that the main takeaway for people is the “the importance of taking care of our bodies.”

“Food isn’t just material to be burned — it’s a signal that tells our body and cells how to respond,” Price said. “We’re getting down to the mechanisms of aging, which may help us make more educated decisions about what we eat.”
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