Scientists find new proteins involved in Huntington's disease

May 14 2007

Researchers in the United States have identified more than 200 new proteins that are involved in Huntington's disease.

Huntington’s disease (HD) is a devastating and fatal hereditary neurological disorder that affects an estimated 30,000 Americans.

If a person inherits a single copy of the gene from a parent, they will develop the disease, usually in middle age; children born to parents who go on to develop Huntington's disease have a 50:50 chance of having the disease themselves.

If a child does not inherit the HD gene, he or she will not develop the disease and cannot pass it to subsequent generations.

The disease results from the degeneration of neurons in certain areas of the brain which in turn causes uncontrolled movements, loss of intellectual faculties, and emotional disturbance.

A person who inherits the HD gene will sooner or later develop the disease and whether one child inherits the gene has no bearing on whether others will or will not inherit the gene.

Early symptoms of HD include mood swings, depression, irritability or trouble driving, learning new things, remembering a fact, or making a decision.

As the disease progresses, concentration on intellectual tasks becomes increasingly difficult and patients may have difficulty feeding themselves and swallowing.

The rate of disease progression varies from person to person.

A genetic test, coupled with a complete medical history and neurological and laboratory tests, helps in diagnosing HD and presymptomic testing is available for individuals who are at risk for carrying the HD gene.

In 1 to 3 percent of individuals with HD, no family history of HD can be found.

Researchers at Baylor College of Medicine (BCM) in Houston, Texas have found that among more than 200 identified proteins which interact with the mutated protein that causes Huntington's disease, some affect the toxicity of HD.

The team studied fruit flies genetically engineered to have a disease that resembles Huntington's in humans and by using high-tech screening of genes and proteins identified 200 that interact with the mutated Huntington's gene.

BCM scientist Dr. Juan Botas, an associate professor of molecular and human genetics, says this could be a way to look for and identify factors that modulate a number of proteins involved in other neurodegenerative disease.

Dr. Juan Botas says such modulating means that the interacting protein affects the deadly symptoms caused by Huntington's; he says some of the interactive proteins might cause a person to develop the disease later while others could actually make the symptoms appear earlier or to be more severe.

Botas and his colleagues say the number of proteins identified could open the door to further research.

The research is published in the journal Public Library of Science Genetics.