By Keith Mulvihill

NEW YORK, Mar 22 (Reuters Health) - Researchers think they have discovered exactly how the gene for Huntington's disease wreaks havoc in the brain and the finding may one day lead to a treatment for the condition.

Huntington's disease is an incurable genetic disorder afflicting about 35,000 to 50,000 people in the United States. The disease is characterized by the death of brain cells, usually starting in middle age, which leads to involuntary jerky movements, personality changes and mental deterioration.

Drs. Christopher A. Ross and Ted M. Dawson of Johns Hopkins University in Baltimore, Maryland, and colleagues discovered that the abnormal protein produced by the Huntington gene mutation--known as huntingtin--affects a second key protein in the brain.

This second protein, known as CBP, promotes survival of brain cells. It appears that CBP gets tangled up in clumps with the huntingtin protein and causes the death of vital nerve cells in one part of the brain, leading to involuntary movements of the body, loss of coordination and cognitive difficulties.

The researchers report their findings in the March 23rd issue of the journal Science.

"Patients with Huntington's disease have a mutant gene called huntingtin that makes a mutant protein called huntingtin. This protein attracts another protein called CBP that is essential to cell survival," Ross explained in an interview with Reuters Health. "We also had data from mice and humans with Huntington's disease that confirmed these findings."

The team of researchers created a synthetic form of CBP that was not attracted to the huntingtin protein. When the new CBP was introduced into cell cultures with a mutated huntingtin gene, the investigators found that normal functioning of CBP could be carried out, Ross noted.

"Instead of degenerating, cells in these cultures remained healthy. We were able to rescue them completely," Ross said.

Since CBP protein can't be taken up by cells in the brain via the bloodstream, administering this protein is not an option for treatment, Ross pointed out. In other words, the new research does not offer a treatment for Huntington's disease, but it does offer a target for drug developers.

"The best hope for a treatment is for a drug that can interfere with the CBP-huntingtin protein attraction," Ross said.

Related MEDLINEplus Pages:

• Huntington's Disease