MIAMI -- A group of scientists at the University of Miami said they have identified nine genes whose presence indicates an increased chance of getting Alzheimer's disease.

More than 5 million Americans have Alzheimer's disease, and many more worry they could fall prey to it. Dr. Margaret Pericak-Vance is on the team of 15 scientists at UM's Institute for Human Genomics who claimed the discovery, which can offer both groups some hope.

"We found certain variations, variations of certain genes, that seem to be present more frequently in cases of Alzheimer's than in what we call control individuals -- individuals who don't have dementia or Alzheimer's dementia," Pericak-Vance said.

Fifteen years ago, Pericak-Vance was part of a team that first identified a protein connected to Alzheimer's disease, a condition that can be treated but not cured.

"Now we can take a more, not quite a shot in the dark, but we have more of a map to follow to get to where we're going, kind of like how everybody's got their GPS unit now," Pericak-Vance said. "We're trying to put together a GPS unit, a scientific GPS."

The genetic research on Alzheimer's disease done at UM has some real-life applications. Pericak-Vance said it will help alert people who might be prone to the disease and allow them to get early treatment.

"There are some therapies or some treatments where the earlier you start, the better the effect they have," she said. "So if you can pick up somebody early in the progress and start using some of these drugs, etc., it may have a more lasting effect."

Pericak-Vance said people as young as 30 years old whose families have a history of Alzheimer's disease can undergo genetic testing to find out if the genes are present. If they are, the patients can start taking medication, change their diets and exercise daily in the hope of preventing the disease, she said.