News at Medicine - July 2020 - Finding a link: PhD graduate part of genetics study providing hope to cancer patients

Finding a link: PhD graduate part of genetics study providing hope to cancer patients
July 21, 2020
New research from the Faculty of Medicine allows women to make better decisions when it comes to preventive surgeries and screenings for hereditary breast and ovarian cancer.
Newly minted PhD graduate Dr. Kerri Smith says that is good news for Newfoundland and Labrador, which has one of the highest rates of both forms of cancer.
“It is exciting to be part of such an important study,” she told the Gazette during a conversation.

Predisposed to cancer

Dr. Smith, who also completed her undergraduate and master’s degrees at Memorial, is playing a key role in a study led by the faculty’s Hereditary Breast and Ovarian Cancer team, led by principal investigators Drs. Lesa DawsonTerry-Lynn Young and Darren O’Rielly.
The group is focusing its research on identifying novel genetic variants associated with those forms of cancer in Newfoundland and Labrador families. The researchers are using a variety of molecular and genetic techniques to prove that the genetic variants are pathogenic – meaning disease causing – and are therefore predisposed to cancer.

Dr. Kerri Smith says she’s grateful for the opportunity to expand her research skills as part of the team. 

Dr. Smith says their most recent work focused on a variant form of the gene RAD51C, which is important for DNA repair. “This particular RAD51C variant was identified in a number of Newfoundland and Labrador women with breast and ovarian cancer,” said Dr. Smith, who is originally from Pasadena on the province’s West Coast.
“The fact that the variant occurred in multiple affected women in families with pedigrees suggestive of hereditary breast and ovarian cancer made us suspicious as to its potential role as a pathogenic variant.”

Preventive recommendations

Examining patient samples, Dr. Smith says she and her research colleagues were able to show that women carrying one copy of the variant have lower levels of RAD51C gene and protein than normal samples.

“Women with this variant are able to make genetic counsellor-guided decisions.”— Dr. Kerri Smith

The results suggest that DNA repair is likely impaired in those individuals. Dr. Smith says the group’s research, which has received financial support from the Belles with Balls, a local community-based group that raises funds to support ovarian cancer research and education, and the Canadian Breast Cancer Foundation, proves the variant is linked to this province’s founder population.
“In all, we gathered a strong body of evidence that suggested this variant causes breast and ovarian cancer in the families studied and that it should be re-classified as a pathogenic variant,” she explained.
“By re-classifying the RAD51C variant as pathogenic, Newfoundland and Labrador women with this variant are able to make genetic counsellor-guided decisions about recommendations for preventive surgeries and cancer screening.”
Dr. Smith says that other family members can also be screened for the variant and that, hopefully, these factors lead to the prevention of future cancers in those individuals.
This information applies to families at risk of hereditary breast and ovarian cancer worldwide and, using their evidence providers, are now beginning to reclassify the variant and make recommendations accordingly.
The group’s research was published online in November in Molecular Genetics and Genomic Medicine.
“Aprominent genetic testing company reached out to us around the time of our article’s publication,” said Dr. Smith. “It used our data to re-issue genetic testing reports to Canadian patients with this variant so they can make informed decisions about their health.”

Specialized laboratory

Dr. Smith says she’s grateful for the opportunity to expand her research skills and be a part of a study that will make a difference in the lives of patients.
She says having a specialized laboratory dedicated to translational genomics – such as the one at Memorial – is necessary for the project’s continued success.
“Ultimately I would like to work in a senior scientist role as part of a team working on hereditary cancer and rare disease research, which are my main scientific interests.”