B.C. researchers have developed an improved hereditary cancer test, which allows for more accurate prediction on "which parent's genes led to an individual's increased cancer risk," according to Provincial Health Services.
While less than 10 per cent of all cancer is hereditary, for those who are affected, this the first time such predictions have been possible, according to the PHS.
“Being able to assign the parent of origin to cancer variants allows us to rapidly identify other family members who may be at risk,” said Dr. Kasmintan Schrader, an assistant professor of medical genetics at the University of British Columbia and co-medical director of the Provincial Hereditary Cancer Program at BC Cancer.
The research, published in the scientific journal Cell Genomics last week, has the potential to improve the diagnosis and management of many genetic diseases, according to the authors.
Schrader's co-author, Dr. Louis Lefebvre — also an associate professor of medical genetics at UBC — says human chromosomes have marks that show whether they came from an individuals mother or our father.
“The challenge is that over the three billion base pairs that represent our genome, only approximately 190 tiny regions contain these parental marks,” he said in a written statement.
That's where technology developed by Dr. Peter Lansdorp, a geneticist at the BC Cancer Research Institute’s Terry Fox Laboratory, comes in. His new long-read sequencing technology allows scientists to determine "subtle functional alterations in DNA," according to Dr. Steven Jones, co-director of the Genome Sciences Centre and professor of medical genetics at UBC.
The implications from the test could be life-altering for many Canadians who carry damaged variants of genes considered very high risk of developing into cancer. Such people currently face a life-time of hospital visits to screen and test for the early onset of tumours. But those high-risk genes are only dangerous if inherited from the father.
In practice, the new test can confirm whether a cancer-triggering gene is present in a patient and what side of the family tree it came from.
"This new approach will eliminate the unnecessary psychological burden of needing to test family members on the other side who are not at an increased risk, reduce the need for clinical counselling and focus resources on identifying and supporting those truly at risk," said Schrader.
