By Emma Wilkinson
Health reporter, BBC News
The risk of a man developing prostate cancer is greater if he has a father or brother who has been diagnosed with the disease under the age of 60.
Laurie Whelan (with wife Jan) has a family history of prostate cancer
Now researchers have identified seven genes linked to prostate cancer which they hope they can be used to screen men to assess their chances of developing the condition.
It is hoped the test will be an improvement on the current prostate specific antigen (PSA) test, which is notoriously inaccurate.
Laurie Whelan, who took part in the genetic risk study, was diagnosed with prostate cancer in 1997 after his younger brother was diagnosed and urged him to be tested.
His older brother had also died from the disease at the age of 53.
Although Mr Whelan had no obvious symptoms, a biopsy confirmed he had advanced cancer, and he had to undergo hormone therapy followed by radiotherapy.
"I have three sons in their 40s who are considered to be at high risk and one has had a PSA test which came back negative.
"I think he and the others should have regular testing.
Taking part in this study has been very interesting and I'm glad to see it's produced such exciting results
"I didn't think I had any symptoms.
"Everything seemed perfectly normal for my age, but looking back I did have some symptoms."
He says he is delighted to have been given the chance to take part in the study.
"It seems to be an important step forward.
"I know we don't have immediate prospects but I'm confident in due course these things will happen."
Mr Whelan, who is now retired but worked as a lab technician in a London hospital, now has a low PSA level and it appears his cancer has not spread.
"PSA causes a lot of uncertainty and worry as the majority who have raised PSA will not have cancer.
"I am anxious about the future for my three sons.
"Taking part in this study has been very interesting and I'm glad to see it's produced such exciting results."
Mr Whelan does not yet know which of the seven high risk genes he may have but hopes to find out once the test is available.