Next of Kin
Thankfully, I work with some very smart people. In fact, I work for one of them, Dr. Stephen Prescott. And when I sat down with him, OMRF’s president told me what I was longing to hear: Don’t worry. “The problem is, people don’t really understand risk at all,” he said.
“It’s like when somebody talks about how risky it is to fly. Is it riskier than staying home? Probably. But it’s much safer than driving a car, and people aren’t too hesitant to get behind the wheel.”
With disease, he explained, we’re too often told about relative risks. “That’s risk by comparison to others, which is what your genome results talked about.” Compared to this group of people, having a certain SNP makes me that much more or less likely than the average Joe to have Disease X. But absolute risk is a different matter.
So, take the bomb I dropped about Lou Gehrig’s disease. What I read in my genome was that my SNPs give me a 30 percent higher relative risk of developing the neurological disorder at some point in my life. On average, about 1 in 100,000 people develop Lou Gehrig’s disease; if my risk goes up 30 percent, my absolute odds are still only 1.3 in 100,000.
I felt a lot better after that discussion. And, once I conveyed it to her, so did my wife.
Sadly, my absolute risk for cancer is much higher. As a man of European descent (my genome tells me I’m 99 percent European), my odds of getting prostate cancer by the time I’m 89 should be 1 in 4. But mine are 1 in 3. And I’ve got higher risk for other types of cancer as well, like a 10 percent chance of getting colorectal cancer before I’m 90.
I won’t lie; those numbers made me nervous. So I went to talk to Dr. Linda Thompson, who holds the Putnam City Schools Distinguished Chair in Cancer Research at OMRF.
Thompson’s research played a key role in creating OncoVue, a genetic-based test to assess breast cancer risk. The test involves a spit-in-the-vial process similar to 23andMe’s. But instead of looking at a half-million SNPs, OncoVue focuses on a panel of 20 to 30 regions of the DNA that have been associated with breast cancer, the ability for DNA to repair itself, and other risk factors for the disease. In conjunction with a lifestyle questionnaire, OncoVue can tell a woman her lifetime risk for developing breast cancer.
The first question Thompson asked me was, “Did they provide you with a genetic counselor?” No, I said. She didn’t much like that answer.
To use OncoVue, she explained, you must agree to talk with a genetic counselor. “They explain the risks, manage expectations and talk about what to do with the information.” For someone who finds she’s at an increased risk for breast cancer, the genetic counselor can help her decide whether the results warrant more frequent mammograms as opposed to, in rare instances, a preventative mastectomy.
“The data genetic tests generate are complicated, and their implications can seem frightening,” Thompson told me. “Whatever the test, it’s important to have some guidance.”
My guide turned out to be Dr. Swapan Nath, who spends his days decoding the genome as a scientist in OMRF’s Arthritis and Immunology Research Program. “Even if part of your DNA says you’re likely to get cancer, there could well be another part that says you’re immune,” he explained.
“You might have genes that will give you protection against cancer—or Lou Gehrig’s disease or all sorts of other conditions. They just may not have been discovered yet.”
In other words, “We still have a lot of work to do.”