Research suggests that almost half of the risk of developing testicular cancer is through DNA inherited from parents.
Scientists now believe that DNA testing could help determine who has an increased risk of contracting the disease, based on their parent's health history.
They say this research could help open up new ways of preventing the disease.
Testicular cancer is more likely to be inherited than other cancer types.
Scientists at The Institute of Cancer Research in London used two independent approaches to analyse the risk of testicular germ cell tumours, which is the most common type of testicular cancer.
The study, which is published in the journal Nature, is the largest ever to look at testicular germ cell tumours in detail.
Scientists analysed data from the Swedish Population Registry cancer family database, which comprises information from 15.7 million people, including 9,324 cases of testicular cancer.
They examined history of testicular cancer in families as well as studying, in great detail, the genetic code of 6,000 men from the UK featured in two previous testicular cancer studies - 986 of these men had been diagnosed with the disease.
SEE ALSO:
'Game Of Balls' Porn Film Has An Unexpected Testicular Cancer Lesson
'I Wouldn't Have Made It Without Being Positive' Says 17-Year-Old Testicular Cancer Survivor
Their research, which was funded by the Movember Foundation, the Institute Of Cancer Research (ICR) and Cancer Research UK, found that nearly half (49%) of all the possible factors contributing to testicular cancer risk are inherited.
This, they believe, is down to a large number of minor variations in a man's DNA code, rather than one faulty gene.
"Our study has shown that testicular cancer is a strongly heritable disease," said Dr Clare Turnbull, senior researcher in genetics and epidemiology at the ICR.
"Around half of a man’s risk of developing testicular cancer comes from the genes he inherits from his parents – with environmental and behavioural factors contributing to the other half.
"Our findings have important implications in that they show that if we can discover these genetic causes, screening of men with a family history of testicular cancer could help to diagnose those at greatest risk, and help them to manage that risk."
She added that the study shows that more work needs to be done.
"There are a lot of genetic factors that cause testicular cancer which we are yet to find," she said. "So the first step must be to identify the genetic drivers of testicular cancer so we can develop new ways to prevent it."
