Fifty-Fifty: Whether to Test for Huntington's Disease
“I had no idea which of my parents carried the gene,” writer Mona Gable recounts. But the death of her brother led her to find out if she carried the marker.
Listen to Life in the Data, Episode 1, featuring Mona Gable:
UNTIL HE DIED in 2010, my brother was often mistaken for being drunk. There were the frequent car accidents, the flashes of anger, the cloudy thinking, and especially Jim’s wild body movements and slurred speech. People would stare after him as he lurched and wove down the sidewalk. We thought his illness was the result of a snowboarding head injury. When I’d press Jim about his health, he would deflect my questions. “I’m better,” he insisted.
Then Jim was dying. As I sat in the pale winter light of a hospital room in Colorado with my sister-in-law, she confessed that for years she’d suspected he suffered from a deadly hereditary disease. I forced the truth from his doctor: my brother had Huntington’s disease. I didn’t know exactly what Huntington’s was, but I knew it was an irrevocable death sentence.
There was no time to focus on what the word hereditary might mean for the rest of my family. I had to call Jim’s close friends. I had to rearrange my work schedule. My brother had no health insurance, so we needed to figure out how we were going to cover the bills.
In the hospital, Jim never complained. Mostly, he slept, while I walked the corridors, snapping photos of the snow-glazed Rockies and the big Western sky. Caring for Jim helped stave off my own terror.
It wasn’t until after his memorial service that I focused on what his diagnosis meant for me. One night I sat down at my computer and did a Google search. Huntington’s is all about the numbers; I learned I had a 50 percent chance of getting the disease. There is no cure. Then I saw the unthinkable: not only might I carry the lethal HD gene, but my children might too.
Huntington’s typically appears in people in their 30s and 40s, but has been seen in patients as young as 2, and as old as 90. Everyone has an HD gene, but those with the disease also carry a defective copy, the impact of which is measured with something called a CAG score. A score of 34 or lower means symptoms won’t be triggered. A score between 35 and 39 means they might. A score of 40 or higher guarantees you will get Huntington’s.
My choice was excruciating: Should I get tested? The disease can’t be treated, so what good would it do? But what about my children? At 18 and 20, they certainly had the right to know if they were confronting a fatal illness.
Nancy Wexler, a neuropsychologist at Columbia University, learned decades ago that she was at risk for Huntington’s. That inspired her to lead the ultimately successful search to identify the HD gene. But the 67-year-old scientist has never been tested herself. “I know that with me,” she said in 2009, “if I were to go to bed every night thinking I’m going to die of Huntington’s … why should I bother getting up?”
Afraid of losing their jobs and health insurance, of being abandoned by loved ones, people with Huntington’s often conceal the disease, as a 2012 study from the University of British Columbia in Vancouver confirms. That fear can lead to parents who don’t get tested unknowingly passing the disease to their children. I had no idea which of my parents had carried the gene; they’d both died years earlier, neither from Huntington’s.
Had my brother know? My sister-in-law insisted that he hadn’t. If he had, though, his fear and loneliness must have been terrible.
On Christmas Eve in 2010, two months after Jim’s death, I sat in a room at UCLA Medical Center with my husband, talking with a genetics counselor. I had decided to take the test, because of my children.
The numbers went my way. I cried with joy. But as grateful as I was, I could not stop thinking about Jim, and the cruel and capricious nature of genetics. He had drawn the wrong number. And it had sentenced him to an awful fate. ★
This story originally appeared in Pacific Standard magazine under the headline, "Fifty-Fifty."