Even hearing the phrase “Huntington’s disease” will make a room suddenly somber. So the joy that accompanied a recent announcement of results of an experimental gene therapy for the deadly diseases signaled an unfamiliar sense of hope.

In a small clinical trial, brain injections of a virus that codes for a tiny segment of RNA may have prevented the formation of the rogue proteins that make Huntington’s so devastating. The early results, announced September 24 in a news release, show that over three years, the treatment slowed Huntington’s progression by up to 75 percent. While not a cure, the treatment could potentially give people living with Huntington’s disease, who might otherwise face early disability and death, the gift of many more years of life.