05a Health

A preprint describing genetically edited human embryos is raising concerns among scientists that the U.S. is becoming more accepting of using gene editing to enhance embryos.

“The cat’s out of the bag,” says Alexis Komor, deputy director of the Sanford Stem Cell Innovation Center at the University of California, San Diego, who was not involved in the new finding.

A team of researchers, led by senior author and Columbia University cell biology researcher Dieter Egli, used base editing—a form of gene editing that involves small cuts to a single strand of DNA—to edit two genomic sites in human zygotes, or embryos at the single-cell stage, that correspond to PCSK9, a gene that regulates cholesterol, and HBG1 and HBG2, two genes that are responsible for the fetal form of the oxygen-carrying protein hemoglobin. The genes were chosen because they were well-studied, not for potential therapeutic purposes, the investigators wrote in the preprint. The experiment was first reported by the New York Times.

Scientists already understand a great deal about the makeup and function of blood cells in humans and mice thanks to advances in hematology and immunology. What has remained unclear is how these cells first appeared and evolved over time. To answer those questions, researchers at Kyoto University set out to trace the origins and diversification of blood cells across the animal world.

Using magnetic resonance imaging (MRI), the team found that the striatum was about 10 percent larger on average in psychopathic individuals compared with a control group. The striatum sits deep in the forebrain and plays a role in movement planning, decision-making, motivation, reinforcement, and how the brain responds to rewards.

Researchers from the laboratory of Roberta Gualdani at the University of Louvain in Brussels identified an unexpected role for a molecule known as TRPV4 in itch triggered by mechanical stimulation, such as scratching.

“We were initially studying TRPV4 in the context of pain,” Gualdani explained. “But instead of a pain phenotype, what emerged very clearly was a disruption of itch, specifically, how scratching behavior is regulated.”