New Drugs May Transform Down Syndrome

Scientific American   People born with Down syndrome have always been considered to be incurably developmentally delayed—until now. In the past few years a number of laboratories have uncovered critical drug targets within disabled chemical pathways in the brain that might be restored with medication. At least two clinical trials are currently studying the effects of such treatments on people with Down syndrome. Now geneticist Roger Reeves of Johns Hopkins University may have stumbled on another drug target—this one with the potential to correct the learning and memory deficits so central to the condition.[...]

Reeves's team injected newborn Down mice with a chemical that stimulates an important neurodevelopmental pathway that, among other things, orchestrates cerebellum growth. “We were not in fact surprised that we fixed the cerebellum. That was our working hypothesis,” Reeves says. Yet he had not anticipated that three months after treatment the mice with a restored cerebellum would be able to learn their way around a water maze—a function of learning and memory thought to be controlled by another part of the brain, the hippocampus. The researchers do not yet know whether they inadvertently repaired the hippocampus or whether the cerebellum might be responsible for more learning and memory functions than previously realized.

In fact, other investigational treatments for Down syndrome target the hippocampus—but none target this particular chemical pathway. Reeves's study, published recently in Science Translational Medicine, may point to a pharmaceutical intervention that could allow those with Down syndrome to live more independent lives. “The possibility of actually giving Down syndrome people the ability to improve learning and memory significantly—that's something I never thought I'd see in my entire career,” he says. “And it's now happening. The game has changed.