Tracy Hutchinson knew the odds before she walked into the genetic counselor’s office. Her older sister Rebecca had died of leukemia at 25. Her mother had survived breast cancer twice only to succumb to esophageal cancer later. Her other sister had just been diagnosed with triple-negative breast cancer, fast-growing and aggressive. When the test came back in 2022, Tracy was 47 years old and finally had an answer: Li-Fraumeni syndrome, caused by a mutation in the TP53 gene.
“It felt like peace,” she told New Scientist’s Alice Klein. “I finally had an explanation for all the cancer in my family.”
Li-Fraumeni syndrome is one of the most devastating known genetic predispositions. The TP53 gene, often called the “guardian of the genome,” normally produces the p53 protein that repairs DNA damage, halts cell division when something goes wrong, and triggers apoptosis when a cell is beyond repair. A single inherited mutation disables this tumor suppressor, leaving cells free to accumulate damage unchecked. The condition is autosomal dominant, one mutated copy is enough.
For women with Li-Fraumeni syndrome, the lifetime cancer risk approaches 100 percent, meaning it is not a question of if, but when and where. For men, the risk is about 70 percent. Half of all people with the mutation will develop cancer before age 30. The cancers that arise can be anywhere in the body: breast, brain, bone, soft tissue, blood, adrenal glands, gastrointestinal tract, skin.
A different kind of vigilance
Unlike BRCA mutation carriers, whose cancers are largely limited to breast and ovarian tissue, Li-Fraumeni patients face a body-wide threat. This makes standard cancer screening inadequate, and it makes radiation-based imaging dangerous, TP53-deficient cells are exquisitely sensitive to radiation-induced DNA damage, creating secondary cancers from the very tools meant to detect the first one.
Tracy’s solution is a surveillance protocol run through Omico’s SMOC clinical trial in Australia. Every November, she undergoes a whole-body MRI. Every year, she has skin checks and blood tests. Every two years, she has an endoscopy and colonoscopy. The anxiety, she says, begins months before each scan, what she calls “scanxiety”, starting around July for her November appointment.
But the protocol works. After her preventative double mastectomy, she chose not to have reconstruction, pathology revealed two early ductal carcinomas in situ in her left breast. Cancers that would have grown, spread, and potentially killed her had been caught at stage zero.
A second whole-body MRI in 2023 found a 9-millimeter meningioma, a benign brain tumor, which is now being monitored. Colonoscopies have found polyps that were removed before they could turn malignant. Atypical cells in her esophagus are under surveillance.
How rare is rare?
Classic estimates place Li-Fraumeni syndrome at 1 in 5,000 to 1 in 20,000 people, but a landmark 2017 NIH study that screened nearly 64,000 individuals found pathogenic TP53 variants in 0.20 percent of the population, roughly 1 in 500. The discrepancy may be explained by lower-penetrance variants that cause a milder form of the disease, but it also raises the possibility that Li-Fraumeni is far more common than previously recognized.
Tracy’s sister was tested for BRCA mutations first, a common clinical path since BRCA is better known and more frequently covered by insurance. When those tests came back negative, the family pursued TP53 testing instead, leading to Tracy’s diagnosis.
“It was a relief to finally know what we were dealing with,” she said. “You can’t fight what you don’t understand.”
For Tracy, understanding has made all the difference. The surveillance has caught cancer before it could become lethal. She does not have children, Li-Fraumeni carries a 50 percent chance of passing the mutation to each child, and uses her story to advocate for broader genetic testing access.
“I want people to know that having a high cancer risk doesn’t have to mean having a death sentence,” she said. “It means you need a different kind of plan.”
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Source: Klein, A. (2026). I have a 100 per cent chance of getting cancer due to a rare gene. *New Scientist*, June 26 2026. https://www.newscientist.com/article/2532073-i-have-a-100-per-cent-chance-of-getting-cancer-due-to-a-rare-gene/