Editor's note: A small Colombian community could hold one of the keys to finding treatments for Alzheimer's disease. Watch "World's Untold Stories" with a one-hour special "Filling the Blank" January 29 and January 30.
Antioquia, Colombia (CNN) -- It's a cruel disease that strips away a person's identity until they can no longer remember their loved ones or feed themselves. But normally, Alzheimer's does not attack until old age.
For some, though, it strikes early -- beginning its attack in their late 30's. Now, one cluster of Early-onset Alzheimer sufferers in the mountains of Colombia could offer hope to families around the world.
For generations, the families in Antioquia have suffered with the disease, watching loved one after loved one deteriorate to death. Now they might be about to strike back.
Early-onset Alzheimer is a rare form of the disease but its brain lesions are identical to those in the late-onset form so the hope is that a treatment for one could carry over to the other.
Dr. Kenneth Kosik said: "People there are getting the disease generation after generation because they are getting a mutation in one of their genes. It gives us a very big clue in being able to predict who's going to get it."
While it's still too soon to tell, Kosik's team believes the Colombian families could help unlock the mysteries of Alzheimer's, ultimately leading to treatments or preventions.
In the U.S. Julie Noonan Lawson, knows all too well about Early-onset Alzheimer's. Her family carries an Early-onset Alzheimer's gene mutation. Her mother developed the disease in her early 30's.
"So I kind of grew up with Alzheimer's," she said. "And it felt like we had a reprieve for many years, and then it showed up again in my sister Fran. I was like, 'It's back, I see it.' So that was kind of the reintroduction of it, and the realization that it's going to encompass our lives."
When a family carries one of these rare genetic mutations, the children of those who develop Alzheimer's have a 50 percent chance of getting it too. In the meantime, they live with uncertainty and fear.
"If it reappeared in my sister, Fran, could it reappear in me?" Noonan Lawson wondered. "Could it reappear in others?"
Ultimately, three of Noonan Lawson's siblings -- Fran, Maureen and Butch -- developed the disease. And now Kate Preskenis, Maureen's daughter, is worried too.
"When they told us about the gene status, I totally fell silent," Preskenis said. "I quit talking about my family history. I quit talking about Alzheimer's. If people would ask me how mom had died, I would casually say, 'Oh, mom had Alzheimer's.' But I wouldn't say, 'Oh, my grandmother, her twin sister, my mom, my aunt and my uncle.'
"I didn't tell everything anymore, because all of a sudden I realized this reflects on me."
In Antioquia, there is a group of families -- about 5,000 people in all -- who can develop Early-onset Alzheimer's in their 40's, if they carry the mutated gene.
It's the largest concentration of Early-onset Alzheimer's sufferers in the world.
Dr. Francisco Lopera, a Colombian, and Kosik, an American, have worked with the Antioquia families for about 15 years and are now building a team of doctors to test drugs on currently healthy people who carry the gene mutation.
Kosik believes this community could be the key to unlocking the secrets of the disease.
"What we're witnessing here in Colombia with these families, in my opinion, holds many of the answers for Alzheimer's disease all over the world," he said.
"More and more our thinking is, if we're ever going to have any impact on this disease, the treatment must begin early.
"In fact, we must begin to treat this disease before it strikes, and to do that, there's no really better population than the group in Colombia."
The team plans to try out a promising treatment every two years -- on people whose age and genetic background put them at risk of developing Alzheimer's.
Dr. Eric Reiman is helping with the effort. "If after two years, we see no effects on our brain imaging or biomarker measurements, the study is discontinued and the family members get access to the next most promising treatment.
"But if there's an effect on these biological measurements, we continue the study just a little bit longer to show that it (the drug) slows down some of these memory declines. If we can do that, we would have found a treatment to reduce the risk of Alzheimer's disease."
They're screening people in Colombia, choosing candidates who will begin receiving drugs in 2012.
For Lopera, the success of the study can be measured in many ways. "If we can delay the beginning, any delay would be a success... One year, two years, five years...
"There are some studies that predict that if we could delay by five years the beginning of the disease, the prevalence of Alzheimer's in the world would drop 50 percent."
It's a lofty goal, considering the prevalence of Alzheimer's is on the rise, at least in part because people are living longer. According to Alzheimer's Disease International, 36 million people around the world have the disease. And studies show there will be 65 million people affected by 2030, and 115 million by 2050.
Reiman's colleague, Dr. Pierre Tariot, cites a recent World Health Organization report: "Part of the report singled out Alzheimer's Disease as the coming pandemic of Western societies.
"It's by no means the only health care threat that we face, but it's a major one. And if we don't find a way to begin to put it behind us, it will have a devastating effect on individuals."
He added: "I could imagine a future where we might intervene in children to prevent Alzheimer's disease."
All the scientists involved in Antioquia are cautious, but they believe they are heading in the right direction.
Dealing with Alzheimer's costs an estimated $600 billion a year worldwide. That is expected to rise 85 percent by 2030.
So doctors and researchers around the world are feeling the urgency to find a treatment. And so are families who keep watching their loved ones fade away.
Julie Noonan Lawson struggles to be optimistic. "I don't want to be negative, and I continue to participate in research, but do I have a lot of hope? No, because I keep watching my loved ones go away."
Her niece, Kate Preskenis, has a message for the researchers. "I would tell them thank you, I'm scared, hurry. Thank you again... Hurry again... It's not ending... I could have it, my siblings could have it, my cousins could have it and their kids could have it. We've already lost mom and dad... I don't want to lose anyone else."