Dorothy and Doris Wyne, both 76, are identical twins, with the same DNA. But they are not the same. Doris has Alzheimer's disease, while Dorothy doesn't.
Both are part of a Duke University study on memory and aging, the largest systematic Alzheimer's twin study in the United States. Along with more than 400 other twins taking part, Doris and Dorothy Wyne just might hold the key to understanding Alzheimer's. Correspondent Vicki Mabrey reports. At 6:30 a.m. every day Glenn Wyne wakes up his wife Doris. Taking care of Doris is a full-time job, which he has held for most of the last seven years.
Recently, he got his first break. For the first time in more than half a century he took a vacation without his wife. He visited his son Chris in North Carolina - a trip they'd planned for two years. Glenn Wyne is not sure how much his wife understands about what is happening in her life. Sometimes she seems completely aware; other times, she seems oblivious.
The only thing anyone can know for sure is what is visible from the outside: With constant care, Doris Wyne goes through the motions of living a normal life. She is still highly mobile and constantly walks around the house, in an incessant pattern. Glenn Wyne has calculated that she walks as much as seven miles a day.
But since she was diagnosed, her brain's neurons continue to be ravaged by the disease, resulting in a steady erosion of her faculties.
"You want to deny it," says her twin, who does not have Alzheimer's. "But then you have to realize that you can't deny it. You have to face it and go forward."
Doris Wyne knows her sister, but can't remember her name. Her words are monosyllabic. She is incontinent and almost completely reliant on her husband for everything.
The disease has created a tighter connection between the sisters. "We're much closer than we ever were, because I feel that I have to look out for her when it's just the two of us together," Dorothy Wyne says.
While Glenn Wyne was on vacation, Dorothy Wyne was in charge.
At one time Doris Wyne had almost uncontrollable outbursts. Now she takes anti-anxiety and anti-depressant medications to calm her. But nothing can treat or reverse the Alzheimer's disease itself. The research has a long way to go.
"It's really one of the great mysteries of medicine," says Dr. John Breitner, who heads the team that began the Duke University study 10 years ago.
The disease is believed to be genetic. But just because someone inherits a gene for the disease doesn't mean the illness develops. The probability increases with age and is also affected by what researchers refer to as environment, meaning any and all nongenetic factors, according to Breitner.
Researchers at Duke University study twins because identical twins have identical genes. Studying the differences in their lives could help them discover what can trigger the disease's onset or what can help to stave it off.
Extensive histories have been tken of both women in an attempt to find clues hidden within the intriguing world of twins.
Dorothy Wyne says the two sisters were inseparable growing up. Until they were married, they slept in the same bed.
They even picked their husbands together - brothers, in fact, only a year apart themselves: Jay and Glenn Wyne. Over the next 50 years the Wyne twins saw their husbands off to war and welcomed them home again. Each couple had three children and raised them all like brothers and sisters.
By all accounts, the playful, outgoing Doris Wyne was the life of the party. But in 1992, at her 50th wedding anniversary, family members noticed a change. When Doris was examined, she had trouble with many standard tests, including counting backward by seven and finding her way out of the doctor's office.
"She would go out and walk great distances at a high rate of speed, as if she was trying to get some place fast," says her son Chris. Her walks often occurred at night, consistent ith what's called Sundown syndrome, in which agitation increases as evening approaches.
Dorothy Wyne knows that the same fate could befall her. But she tries not to worry about it. To test herself, sometimes she counts backward by seven. When she has moments of forgetfulness, she wonders.
Dr. Breitner says that Dorothy's forgetfulness is only of concern if it increases over time. But he also says that as Doris' identical twin, she has a much greater chance of getting the disease than another 76-year-old would have.
But the Duke research also gives her some hope. The study includes several pairs of twins in which only one has suffered the disease.
The Duke researchers initially expected to find activating agents, like chemical exposures or previous illnesses, that would trigger the patient's genetic predisposition for Alzheimer's. But the only one that they found was head injury.
But the researchers also found certain substances might slow down the disease's onset, including anti-inflammatories. Dorothy Wyne took them for her arthritis more than her sister did. In the study as a whole they seem to inhibit the onset of Alzheimer's. The evidence is preliminary, but Dorothy takes them daily now.
Taking care of Doris was exhausting for Dorothy and her husband, who were happy to see Glenn Wyne when he returned.
For his part, Glenn Wyne has vowed he will never put his wife in a nursing home, which means he must work very hard every day. "I'm not going to give up," he says.
Neither are the researchers. But despite some recent breakthroughs - even hope for a preventative vaccine - the cure is still a long way off. The more immediate challenge, says Breitner, is that caregivers like Glenn Wyne must understand that they are at risk of giving until there's nothing left.
Glenn Wyne, though, believes that he is fully responsible for his wife: "It's rather - well, trite. When they said, 'Do you take each other for better, for worse, in sickness nd in health,' I might have just repeated the words initially without a thought what it's going be like 50 years down the road."
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