• By Susan Murphy

Science Saturday: Conquering cancer by targeting its genetic abnormalities

January 9, 2021
research test tubes containing blood samples

Joanne Garnett has harrowing memories of that life-changing day back in 1981. She was a 39-year-old land use planner living in Wyoming when she received a call from her doctor confirming she had uterine cancer. 

“I was shocked, and it was strange because I didn’t fit any profile for uterine cancer,” Garnett recalls. “I got a complete hysterectomy, and I figured, well, that’s that.” 

But it was just the beginning. A decade later she was struck with stage 2 colon cancer, then kidney cancer. 

“I underwent chemo and radiation, had a portion of my colon removed, then I lost my right kidney, and I thought, 'Who has this kind of luck?'” she says.

As an adoptee, Garnett was not aware of her family medical history or the hereditary genetic mutation lurking deep within her DNA. The discovery came from a simple blood test. 

“I got the results back and it showed, yes, indeed, I had one of the four types of the genetic defect that is Lynch syndrome,” she says.

Lynch syndrome is a cluster of inherited mutations that increases the risk of several cancers, including colorectal, kidney and uterine cancers. It generally strikes before the age of 50. It’s caused by changes to genes that affect DNA mismatch repair — a process that fixes mistakes when DNA is copied. These genes normally protect a person from getting certain cancers, but mutations prevent the genes from working properly.

Discouraged, yet determined, Garnett made an appointment with Niloy Jewel Samadder, M.D., a gastroenterologist and cancer genetics expert with Mayo Clinic Center for Individualized Medicine in Arizona.

“He helped me realize it is a gift that I know that I have Lynch syndrome because now I know what I need to do in order to stay in front of it as much as possible,” says Garnett. “It’s his level of care and diligence and attention that brings me peace at night.”

Read the rest of the article on the Individualized Medicine blog.

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