Fathers could be passing on a genetic mutation to their daughters that increases the inherited risk of ovarian cancer.
In earlier studies, researchers noticed that when a woman develops ovarian cancer, her sister faces a higher risk of also developing the disease than her mother.
Using this observation as a starting point, academics at Roswell Park Comprehensive Cancer Center in New York have investigated whether genes on the X-chromosome, potentially passed down through the father, may contribute to his daughters' risk of ovarian cancer.
With analysis on pairs of granddaughters and grandmothers, they have identified a previously unknown mutation on the X-chromosome that may be associated with cases of ovarian cancer that develop more than six years earlier than average.
"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 Dr. Kevin H. Eng, an assistant professor of oncology.
The study proposes that a gene on the X-chromosome may contribute to a woman's risk of developing ovarian cancer, independently of other known susceptibility genes, such as the BRCA genes.
However, the researchers are now wanting to conduct further studies to confirm the identity and function of this gene.
"What we have to do next is make sure we have the right gene by sequencing more families. This finding has sparked a lot of discussion within our group about how to find these X-linked families. 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," added Dr. Eng.
Full study results have been published in journal PLOS Genetics.