Research Report 2008

That’s some family legacy

Disembarking from the vessels that carried them across the Atlantic, thousands of English and Irish settlers arrived on the rocky coast of the island of Newfoundland ready to start a new life. With them they carried distinct cultures, one-of-a-kind heirlooms and unique genetic patterns. Hundreds of years later, genetic researchers at Memorial are using that heritage to help locate specific gene mutations that result in cancer. The large family sizes so common here helped speed up the research.

A family tree nine pages long (normally captured on a single page) brought home the results with astounding accuracy.

Taking aim at a stomach cancer rate already two times higher than the rest of the country, Dr. Bridget Fernandez and her team in the Faculty of Medicine found that working with families in this province shed light on the genetic transfer of the gene. Finding a connection to lobular breast cancer in that same mutation means even more lives may be saved through the simple act of blood testing.

Dr. David Huntsman, a 1988 alumnus of Memorial’s medical school, is principle author of the study. He was recently awarded a $759,000 five-year grant from the Canadian Cancer Society to focus primarily on families in Newfoundland. His team includes Dr. Fernandez as wells as Andre MacMillan, a genetic counselor with Eastern Health and clinical lecturer with the Faculty of Medicine. The research is helping to determine if special screening programs for a mutation in a gene called CDH1 needs to be developed to protect against breast cancer and stomach cancer.

In previous research funded by the Canadian Cancer Society, Dr. Huntsman and his team, based at the BC Cancer Agency in Vancouver, found that 70 per cent of people with the gene mutation went on to develop stomach cancer. Evidence is now emerging that it may also lead to lobular breast cancer, which accounts for eight to 15 per cent of all breast cancers.

The research team believes the genetic mutation might be the reason the rate of stomach cancer is so much higher here. “I was getting calls from family members but the one in particular that I remember was a woman we were working with whose family is from Placentia Bay. She wanted to bring in 17 of her family members and I remember thinking ‘This is not the scope we’re used to dealing with’,” explains Ms. MacMillan. “That family tree has just gotten bigger and bigger since the start of this project. Normally, I can fit a Newfoundland family tree on one page. Theirs fits on nine pages.” It was the growth of this family tree and their subsequent testing that helped researchers get more accurate results for the study. International collaboration is also taking place to gather additional cases to study.

The mutation is life-threatening for families who have it, said Dr. Huntsman. Gastric cancer is extremely difficult to diagnose and is usually incurable once it is advanced enough to be detected. If his research shows there is a clear link between the mutation and the later development of cancer, screening for it will be as simple as administering a blood test.

“If individuals find they carry the defective gene, they can make decisions about preventive treatment,” he added. “For patients at risk of gastric cancer, that might mean a preventive stomach removal, a strategy that has already proved successful in preventing the disease in more than 50 people.” In the future, Dr. Huntsman hopes that a drug can be developed to target the mutation.

“It’s been both humbling and inspiring to work with these extremely courageous families who have dealt with this dread for generations,” said Dr. Huntsman. “What we’re doing is giving them the tools to face down their fear.”

Copyright © 2008 Memorial University of Newfoundland