A 30-year study found women whose paternal grandmothers were affected by ovarian cancer were at the highest risk of developing the disease.

Women can inherit a genetic mutation that causes ovarian cancer from their fathers as well as their mothers, US scientists have discovered.

A large study of thousands of families impacted by ovarian cancer found the mutation passed down through the father's X chromosome is entirely separate from the BRCA1 and BRCA2 genes and is also associated with higher rates of prostate cancer in fathers and sons.

Published in journal PLOS, the researchers say the findings of the 30-year study may explain why some families have multiple members affected by the disease.

"A family with three daughters who all have ovarian cancer is more likely to be driven by inherited X mutations than by BRCA mutations," said Kevin Eng, a professor of oncology at Roswell Park Comprehensive Cancer Center in Buffalo, New York.

Using the Familial Ovarian Cancer Registry, researchers trawled through data collected over 30 years and collected information about pairs of granddaughters and grandmothers. They then sequenced portions of the X-chromosome from 186 women affected by the cancer.

Women born to fathers who's mother had been affected by ovarian cancer were twice as likely to develop the disease, compared to those who inherited the disease from their mother's side, data showed.

"The paternal-lineage women had 2.04 times the risk of maternal-lineage women," the authors wrote.

Women carrying this previously unknown mutation on the X-chromosome also developed the cancer more than six years earlier than average.

"We observed a significant acceleration in the development of disease in granddaughters with an affected paternal grandmother versus maternal grandmother," wrote the authors.

Further research is now needed to confirm the identity and function of the X-linked gene that contributes to familial transmission of ovarian cancer, Professor Eng says.

"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," he said.