According to new research published in PLOS Genetics, fathers can pass a genetic mutation that increases the risk of ovarian cancer to their daughters. A team of scientists from the Roswell Park Cancer Institute (RPCI) found that a newly discovered genetic mutation is connected to earlier onset of ovarian cancer in women and prostate cancer in fathers and sons because it is passed down through the father's X-chromosome. 

Previous research has shown that when a woman gets ovarian cancer, her sister has a higher risk of developing the disease than their mother, suggesting that perhaps this genetic predisposition is passed down from the father. So Kunle Odunsi and Kevin H. Eng from the RPCI decided to investigate the role of the father's X-chromosome. 

To research this, the scientists looked at data on 3,499 granddaughter/grandmother pairs from the RPCI's Familial Ovarian Cancer Registry, finding 892 informative pairs and 157 granddaughters affected by ovarian cancer. They also sequenced parts of the X-chromosome of 186 women with ovarian cancer. The team discovered that ovarian cancer can be inherited from the paternal grandmother, and that those with the genetic mutation are more likely to develop the cancer early – around six years earlier than average. Additionally, the fathers in-between were found to be more likely to get prostate cancer if their mother had had ovarian cancer. 

The team also revealed that the gene on the X-chromosome can increase the chances of a woman getting ovarian cancer regardless of the presence of other known susceptibility genes like BRCA genes.

“Our study may explain why we find families with multiple affected daughters: because a dad’s chromosomes determine the sex of his children, all of his daughters have to carry the same X-chromosome genes,” said Eng in a statement, adding that more research is needed to ensure the correct gene was identified. 

“This finding has sparked a lot of discussion within our group about how to find these X-linked families," Eng added. "It's an all-or-none kind of pattern: A family with three daughters who all have ovarian cancer is more likely to be driven by inherited X mutations than by BRCA mutations.”