USU researchers assist in Alzheimer’s breakthrough
Utah State University researchers contributed to the biggest breakthrough in understanding Alzheimer’s disease in almost two decades, according to material published recently in the New England Journal of Medicine. Scientists from around the world collaborated in this effort to analyze genetic markers for rare mutations that shed light on how the disease develops.
Christopher Corcoran, a biostatistician on the research team, said for research breakthroughs like this to happen, institutions have to come together and pool their resources. Otherwise, there just isn’t enough data to see the rare genetic mutations that could help determine specific causes of Alzheimer’s disease.
“When you’re studying a disease like Alzheimer’s, you need to have a gigantic sample,” Corcoran said. “You need to have as many individuals as possible. The move over the last five to six years has been to pool samples from across studies to give you a higher probability of identifying effects, identifying new genes.”
This particular discovery concerned a genetic variant referred to as the TREM2 gene which, although rare, increases likelihood of developing Alzheimer’s threefold.
“Before this, there were only a handful of genes that were known to have a very strong effect for Alzheimer’s,” Corcoran said. “It’s the first major gene in a long time that’s been identified for the disease.”
Corcoran said as people pool their resources and collaborate through these kinds of consortia, the resulting giant super samples give them the ability to detect connections which were overlooked before.
USU contributed data from the Cache County Memory Study, a world-famous study on the effects of Alzheimer’s and dementia that was started in 1995 and is ongoing.
According to the USU Center for Epidemiological Studies, The Cache County Memory Study enrolled 50,092 permanent residents of the county – 90 percent participation. Cache County is uniquely suited to this study because the elderly of Cache County have a longer life expectancy, higher educational attainment and lower incidence of chronic disease than similar situations, which can complicate the diagnosis of dementias.
Elizabeth Fauth, an investigator in an ongoing dementia progression study at USU, said the Cache County Memory Study is very unique and valuable because the initial rate of participation in Cache County was so high.
“We’ve been able to get a whole population of people before they get Alzheimer’s disease and then followed them to see who gets it and who doesn’t,” Fauth said. “That’s a very rare kind of study design that most people don’t have.”
Corcoran said genetics has always been a primary source of hypotheses for this study, whether or not certain genes are associated with your risk for Alzheimer’s. He said it’s an exciting time for genetics because knowledge in the field is improving. Research like this has become possible in the last few years due to advancements in the technology of genetics.
“You can now pipe people’s DNA for more markers at a much cheaper cost than when the study started,” Corcoran said. “Back then, it was a big deal to maybe get a genotype for one gene. Now, you can get millions of markers across the human genome for a fraction of the cost.”
Cocoran said when the study started, biological samples were taken from all of the participants and stored for future use. Limited work was done analyzing those samples, but with the advent of new technology, the samples can be analyzed in new ways. In this way, the study continues to gain insight even though many participants in the study have long since passed away, he said.
Fauth said USU’s ongoing research in this field, especially discoveries and publications like this, are very good for the school’s public image as a research university.
“All of these studies together and the fact that they’re published in top tier journals in the field are really making a difference,” Fauth said.
She said they are really drawing a lot of positive attention to USU.
“I would absolutely say that this is one of the best studies in the world,” Fauth said. “It’s very unique. It just has a lot of attributes that other studies are not able to get.”
Alzheimer’s Research UK in London coordinated the global effort. Laura Phipps, a science communications officer for ARUK, said Alzheimer’s is an incredibly complex disease because genetic, environmental and lifestyle risk factors all contribute to its development.
“Understanding these risk factors can help us understand more about the disease, what causes it and what might make it develop faster,” Phipps said. “By unraveling this, we can start to develop health messages to help people lower their risk or design new treatments to slow or stop the disease.”
Phipps said the main gene linked to Alzheimer’s disease was discovered by scientists in the early 1990’s. People who have one copy of the gene, called APOE4, are around three times more likely to develop the disease. Phipps said there hadn’t been any major developments since the APOE4 breakthrough until now.
“Over the past couple of years, research has found around nine genes which are linked to a higher or lower risk of Alzheimer’s but the risk they confer is very small, around 1.2 fold,” Phipps said. “The TREM2 gene discovered here has a threefold risk, so similar to that of APOE4 discovered over 20 years ago.”
– abhendrix@pentaracorp.com