Chastain family reunites, learns about Alzheimer’s disease (with video)
Angie Mayes • Special to The Democrat
Dec 15, 2015 at 3:20 PM
More than 100 descendents of original Middle Tennessee settler Pierre Chastain met in Lebanon on Saturday for a family reunion, but this was more than just an average family reunion.
A significant number of members of the Chastain family – have for years – developed dementia and Alzheimer’s disease. There’s no explanation why, but scientists at Emory University are studying the family to try to find the defective genome in their DNA.
After an hour-long presentation by Thomas Wingo, a researcher studying the Chastain family, members of the family gave blood to have themselves tested for a research study he and other researchers are conducting. At the end of the study, they will publish a paper on the family and subject.
Not only have some members donated blood, some deceased members with Alzheimer’s have donated their brains to study.
Wingo is assistant professor of neurology and human genetics at Emory University and works at the Emory Center for Neurodegenerative Disease. He is an Atlanta Veterans Administration investigator whose research laboratory is primarily based at the Center for Neurodegenerative Disease.
His post-doctoral training focused using both classical and emerging genetic techniques – next-generation sequencing – to the study of neurodegenerative illnesses that cause impairments in memory and cognition. He is a board-certified neurologist with additional training in cognitive neurology and sees patients at the Atlanta VA Memory Clinic.
Wingo is focused on finding new genetic causes of Alzheimer’s disease and front otemporal dementia. His goal is to find and fight the causes of the illnesses.
To do this, he focuses on young-onset Alzheimer’s disease genetics. Most of the causes of young-onset Alzheimer’s disease, meaning onset on or before 60 years old, are not known. However, about 10 percent of individuals with young-onset Alzheimer’s, also called early onset Alzheimer’s, comes from families with apparent autosomal dominant transmission of the illness.
He also studies late-onset Alzheimer’s disease genetics. The common form of Alzheimer’s disease has a substantial genetic basis. Unlike young-onset Alzheimer’s, late-onset Alzheimer’s is due to the cumulative effect of 1,000s or 10,000s of genetic changes. However, there still appear to be families that transmit the illness as an autosomal dominant trait. The Emory ADRC has collected a number of large families and, using linkage and next-generation sequencing techniques, are moving to identify high-risk alleles in these families.
According to pickensprogressonline.com, the “Descendants of Pierre Chastain who in Pickens and Gilmer counties unroll their extensive family tree. Top researcher Dr. Allan Levey at Emory’s Alzheimer’s Disease Research Center believes studying the Chastain family’s genetics could lead to breakthroughs in the field.
“The Chastain family bloodline defies anything,” said Levey. “In terms of what we would consider a strong genetic trait, this family way beats the odds. I don’t know another family with such a high prevalence.”
For more than a decade Levey and his research team at Emory have studied descendants of Pierre Chastain because of the astonishingly high rate which they develop the disease. Alzheimer’s affects 50 percent or more of the family, which, after 10 generations, has branched into north Georgia, including Pickens, Alabama and the Carolinas.
The family study is especially important, Levey said, because the Chastains develop the more common late-onset Alzheimer’s – just like 90 percent of all people who develop the disease.
“There are some very, very rare families that have been studied who have members who get Alzheimer’s at a young age,” Levey said, “And these families have led to the discovery of three genes that cause Alzheimer’s. This was a huge breakthrough. The Chastain family has the strong genetic basis, as well, but also has the more typical late-onset and this means they could be even more important in terms of research.
“The discovery of the gene in their family will let us have an understanding of Alzheimer’s and how it occurs in others. In those rare families with young onset we inferred from [their genes]. It is important to learn the process of what’s going awry in the brain. Finding this gene could lead to future breakthroughs.”
Levey said anyone with the Chastain name is believed to be of the Pierre Chastain bloodline. All members of the Chastain family are desired for the study, but those older than 70 who have not developed Alzheimer’s symptoms are particularly important.
“We need to compare those family members with and without the gene,” he said. “Those older members without memory problems are the ideal candidates, but we definitely encourage everyone to participate.”
As part of their ongoing research Levey and his team have developed a strong connection with the Chastains. They attend family reunions where they draw blood. Just last month, researchers traveled to Ellijay, Ga. and made a presentation to members of the family about Alzheimer’s and their family’s significance in the field.
Along with the research, the family members were allowed to tour the former home of Elisha Chastain, who is Pierre’s grandson. Hugh and Marsha Midgett now own the home.
“Just two weeks before our wedding, this 400-acre property across the road from Hugh’s parents’ farm was tracked off into small lots with one lot of 50 acres and a house,” Marsha Midgett said. “We decided we would start farming right here where he was raised. We were both agriculture majors and bought the 50-acre tract.
“The property had been neglected and had renters in the house for the past several years before we bought it. You couldn’t even get down the driveway. It was in such bad repair. We slowly repaired and replaced as we could afford it.”
In 1982, the Midgetts did a major renovation and rehabbed the log house.
“Up to that point, we were using the log house to strip tobacco in while living in the frame wing that was added on it in the ‘60s,” Marsha Midgett said. “We both loved history and at times, we found ourselves not renovating, but reading the layers and layers of old newspaper that was plastered to the walls. For young people as we were then, it was quite an adventure. Having done archeological work as a teenager, it was so exciting to discover so many artifacts from the previous owners throughout the years. The fun still continues as we find objects still to this day.”
She said they are “both excited to share our home with [the Chastain family], the original owner’s descendants. We hope you will feel it is your home, too.”