KENAI, Alaska - He knew about the high possibility of a genetic disorder being passed down to him since his early 20s. Jason Johnston, 33, recalled visiting his grandmother, Clarice Phillips, in a nursing home during that time.
"I don't remember much except she couldn't control her body movements and didn't recognize my mom," said Jason, who was diagnosed with Huntington's disease last year. "Didn't even recognize her own child ... It was pretty hard on my mom."
Support avenues for Huntington's disease are sparse in Alaska so the Johnston family is planning a walk to raise funds for awareness and research. Jason has joined a clinical trial focusing on the disorder and hopes to attain help for others, including his children, who have a 50 percent chance of developing the disease.
Huntington's is caused by a genetic defect on a person's fourth chromosome pair. The defect causes a part of the DNA, called a CAG repeat, to occur more times than nor mal, or more times than it's supposed to. This section of DNA normally is repeated ten to 28 times. In people with the disease the repeat occurs 36 to 120 times, according to Huntington's Disease Society of America.
Symptoms include behavioral changes, like moodiness, paranoia and psychosis; abnormal and unusual movements, like jerking movements of body parts and turning of the head to shift eye position; and dementia that gradually gets worse. Those symptoms are a result of the nerve cells in certain parts of the brain wasting away, or degenerating.
The disease affects everyone differently, but people with Huntington's generally die within 15 to 20 years from the onset of symptoms.
"There's no set time frame," said Corrine Johnston, Jason's wife.
According to the National Institutes of Health, as the gene is passed down through families, the number of CAG repeats tends to get larger. The larger the number of repeats, the greater the chance of developing symp toms at an earlier age.
Although prevalent through multiple generations, the disease has affected the Johnston family inconsistently. Grandma Phillips was in her late 50s when she died, Jason recalled. His mother, Charlotte Johnston, 58, is progressing slowly.
She's wheelchair bound, weighs 95 pounds and has trouble swallowing food. Charlotte weathers her afflictions in stride, Jason said.
"She can barely eat her food, but every time we come through the door she smiles," he said. "She's never worried about herself; she's always been concerned about other people."
Charlotte's two sisters and brother lived with Huntington's disease, too. Her 38-year-old daughter and Jason's sister, Amy Everhard, is beginning to experience mild symptoms.
There are two forms of Huntington's disease. The most common is adult-onset, with people who develop symptoms in their mid-30s and 40s. An early-onset form of Huntington's accounts for a small number of cases and begins in childhood or adolescence, according to the National Institutes of Health.
Last year, Jason joined a clinical study conducted through Huntington's Disease Society of America as an effort to identify symptoms earlier in carriers' lives. During his visit to the clinic in Indiana, he saw a neurologist, who diagnosed him as having symptoms.
Jason's symptoms include involuntary muscle movement. He also experienced an uneven temperament but is now on medication.
"I was moody there for a little bit," he said.
Depression and thoughts of suicide are common among people with the disease. Dopamine blockers are used to reduce abnormal behaviors and movements. People with Huntington's often commit suicide, but the most common cause of death is infection.
"All the doctors can do is attempt to treat the symptoms; there is no actual treatment or cure for Huntington's disease," Corrine said.
Receiving the diagnosis was one of the lowest days in Jason's life. Explaining the disease to his 11-year-old daughter, Courtney, also was taxing, he said. Her first question was whether or not she or her younger brother, Vance, could get the disease.
Then there was the phone call. Jason works for BP Alaska, and while on the North Slope his son called him, crying in confusion about his father dying from sickness.
"I don't know if he really grasps the whole concept at 6 years old, but he knew enough to figure it out," Jason said.
The North Slope worker has since come to peace with his affliction. He wants to help his children and others, which is why he joined the prediction study.
"At this point, I know I'm not going to be cured," he said. "God's helped me through that.
"I just want to help my kids and people who've been diagnosed to find a cure or at least improve their treatment."
"My plan is to reach as many people as possible," Corrine said.