After discovering that she had a BRCA gene mutation, making her more likely to develop breast and ovarian cancer, Emma Simons organised a BRCA awareness evening at Cockfosters and North Southgate Synagogue that was attended by 130 people.

"This is a conversation we should be having," Mrs Simons, 41, said. "It shouldn't be an unknown, especially as we are at a higher risk of having this gene."

Ashkenazi Jews are 20 times more likely to have harmful mutations in the tumour-suppressing BRCA1 or BRCA2 genes. And if either parent has a mutation, there is a 50 per cent chance of it being passed on.

Mrs Simons - who has three children between the ages of five and 10 - would ideally liked to have had a fourth child. But to protect herself against cancer, she this week underwent elective surgery to remove her ovaries.

Speaking beforehand, she said she was "a bit scared" but confident she had made the right decision. "I'm removing healthy parts of me but I could get ovarian cancer and wouldn't know until the later stages.

"I know I'm at a significantly higher risk - I have an 85 per cent lifetime risk of getting cancer - so why not take away that risk and have preventative surgery, so the kids never see me go through that?"

As well as the awareness evening - addressed by surgeons, researchers and counsellors from Barts Cancer Institute and University College London - the synagogue also held a "Pink Shabbat" to further educate the community. "We're lucky we have a rabbi and rebbetzin [Daniel and Ilana Epstein] who talk about this."