According to a team of researchers from the Roswell Park Cancer Institute, a new gene mutation could be responsible for ovarian cancers and this could be passed on from fathers to their daughters.
The gene in question is passed via the X chromosome that comes from the father to the daughter. It has been seen to be independent of the other genes that predict ovarian cancer risk. This remains a preliminary study and more research is necessary to prove this connection say the researchers. The study results appear in the latest issue of the journal PloS Genetics.
At present the BRCA gene is one of the strongest predictors of cancers in the family among women - notably breast and ovarian cancers. Angelina Jolie for example underwent a preventive removal of her breasts and ovaries because she had the said gene that raised her risk of breast cancer to 87 percent and ovarian cancer to 50 percent. Researchers have now found that there are several cases of ovarian cancers where these BRCA genes may not be the carriers, but a separate gene may be the culprit. These genes are found in the X chromosome that the father passes on to his daughter, they note.
Dr Kevin Eng and colleagues found that one gene in particular came up again and again – the MAGEC3 that was found on the X chromosome from fathers. They found that ovarian cancers that came from mothers to daughters had a later onset in life compared to those that came from fathers and paternal grandmothers. These genes were also associated with an increased risk of prostate cancers among sons when inherited from fathers.
Lead author Kevin Eng from the Roswell Park Comprehensive Cancer Centre in Buffalo, New York explained that the next step would be to sequence the genomes of the families to detect the gene and pinpoint it more clearly. They would need more families and their DNA to find the gene he said. He explained that if a family had three daughters, all with ovarian cancers, the most likely explanation would be that they are getting it due to the mutation on their X chromosomes that they inherited from their fathers rather than due to the BRCA mutations, they inherited from their mothers.
According to Dr Catherine Pickworth from Cancer Research UK, this study helps to understand the inheritance of ovarian cancer risk that can also come from father’s family as well. She said that this is important for risk estimation for women because in most women ovarian cancers are detected at later stages when treatment is difficult with little chances of success. Annwen Jones, Chief Executive of Target Ovarian Cancer also lauded the study because it would shed light on ovarian cancer inheritance.
Another study has found that the testing protocols for BRCA gene mutations vary widely across labs. The team led by Amanda Toland, PhD, of The Ohio State University Comprehensive Cancer Center looked at 86 genetic testing laboratories around the world to come to these conclusions. They found that 93 percent used modern sequencing technologies while six labs used traditional Sanger sequencing methods. BRCA1 and BRCA2 genes are responsible for repairing DNA damage. Mutated versions of these genes are responsible for increased risk of cancers. BRCA 1 mutation for example may raise the risk of ovarian cancers by 40 to 50 percent.