Narrator:This is Science Today. Huntington's disease is a devastating neurodegenerative disorder in which a number of neurons in the brain die. This causes symptoms ranging from significant psychiatric changes and trouble reasoning to uncontrolled movements. Lawrence Goldstein, a professor of cellular and molecular medicine at the University of California, San Diego says it's also a hereditary disease.

Goldstein: It's what we call autosomal dominant - so if only one parent has the disease, there's a fifty percent chance that any one of the children will get it a piece. It tends to come on relatively late in life after you've had children - so you didn't know whether you had a risk of passing it on or not.

Narrator: Goldstein and his colleagues have linked a defective protein in Huntington's disease to gridlock in the vital neuronal transportation system, which eventually leads to neuron cell death.

Goldstein: A key first step in the treatment of any disease is learning what is it that's failed and why? And then you can start to develop interventions that hopefully will have therapeutic benefit.

Narrator: For Science Today, I'm Larissa Branin.