New Alzheimer's Gene Found

The discovery of a new genetic risk factor for Alzheimer's disease may put researchers one step closer to understanding the degenerative condition.

Research published in the upcoming issue of Nature Genetics reveals a gene variation that is associated with an increased risk for late onset Alzheimer's -- the most common form of the disease.

But while the finding provides another positive development, Alzheimer's disease experts caution that applications for diagnosis and treatment are still speculative.

"There have been many linkage studies, and this is new but not stronger than others," said Dr. Norman Foster, director of the Center for Alzheimer's Care, Imaging and Research at the University of Utah. "It is very premature to consider any treatment approaches."

Yet, the advancement could help researchers continue to assemble a more complete picture of the disease's causes and origins.

"It is still necessary to know of every gene that is involved in AD risk," said Rudy Tanzi, of the Mass General Institute of Neurodegenerative Disease in Cambridge, Mass. "No matter what the effect on risk, each fills in a piece of the puzzle regarding the biological underpinnings of the disease."

"The article represents a significant finding in the growing search for the genetics of Alzheimer's disease," said Dr. Paul Kettl, professor of psychiatry at the Penn State College of Medicine. "It is clear that AD has a significant genetic component in many individuals, and this paper adds to the growing data on the subject."

Small Steps Add Up to Greater Understanding

The discovery of this genetic risk factor is the latest in a recent string of potential advances in understanding Alzheimer's. Researchers have also studied the promise of PET scans and spinal fluid tests in identifying the disease.

In this newest study, researchers suggest that faulty versions of a particular gene -- called SORL1 -- contribute to formation of amyloid plaques, which are tangled masses of protein that form on nerves in the brain.

These plaques are hallmark signs of Alzheimer's, and some believe they may even cause the disease.

"This finding is preliminary and may or may not hold up over time," says Dr. Rachelle Smith Doody of the Baylor College of Medicine's Alzheimer's Disease Center. "If it does, it is likely to shed light on the mechanisms by which altered amyloid processing can lead to Alzheimer's disease."

And the hope is that tests may eventually be developed that could detect susceptibility to Alzheimer's early, allowing for early intervention and -- possibly -- treatment.

Testing, Treatment Still Prospective

Despite the promise of this new finding, current Alzheimer's patients and their families will not likely reap the true benefits of this research.

"Researchers are continuing to unlock the mysteries of the disease," said Dr. Kettl. "This study provides more data about the disease, and provides some hopeful avenues for future treatment.

"However, it should be remembered that even if this article provides vitally important data, any treatment coming from this is years away -- probably, it is far enough away that those who are now suffering from the disease would not be affected by its findings."