Gene Therapy, Successful Against Parkinson's, Continues on the Road to Redemption

Back in the 1980s, gene therapy was one of science’s greatest hopes and hypes, and researchers predicted the technique would be used to cure a huge range of illnesses. During the 90s, many early gene therapy trials were effective or downright dangerous, some causing cancer or even death. But more recently, scientists who stuck with gene therapy have started to see positive results, with promising treatments for malformed hemoglobin, color blindness, and depression. (See the DISCOVER magazine feature “The Second Coming of Gene Therapy” for more.) Now, researchers have announced that they’ve successfully treated the symptoms of Parkinson’s disease in a small group of people—a far cry from a cure, but still a step in the right direction.

I Once Was Blind but Now I See

The theory behind gene therapy is simple: A healthy gene hitches a ride into the patient’s genome on a virus, replacing the genes responsible for some genetic disease or disorder. Actually doing this is more difficult, because humans have a little thing called an immune system that’s remarkably efficient at finding and destroying foreign bodies. After the first U.S. death from gene therapy in 1999, and leukemia cases in France the same year, many started to think that gene therapy was more of a problem than an answer.

The early and awful failures forced all of the researchers in the field to retreat and reconsider the staggering complexity that challenged them. They could not just replace a bad gene with a good gene, as some early pundits had hoped—they also had to orchestrate the nuanced and elaborate dance between the gene products (proteins) and the patient’s immune system, which could recognize a foreign body and viciously attack it. After that was settled, gene therapists still had to find a suitable virus, or vector, to carry replacement genes into human cells without inciting a damaging or deadly immune response…. It was this new perspective more than anything else that turned gene therapy from a simple but failed and frustrated hope into, once again, medicine’s next big thing—a stunning spectacle of hubris, ignominy, and redemption on the scientific stage. [DISCOVER]

New: Gene Therapy and Parkinson’s Disease

While there’s no cure for Parkinson’s as of yet, doctors have an arsenal of methods, ranging from drugs, brain stimulation, and (now) gene therapy that help reduce the disease’s symptoms. Hopes for using gene therapy to alleviate Parkinson’s effects aren’t new. What is new is that scientists have successfully completed the first randomized, controlled, double-blind trial of treating Parkison’s patients with gene therapy—and they found that it significantly improved debilitating symptoms such as tremors, motor skill problems, and rigidity. Read More