Simple blood tests offer telling signs of someone's genetic risk for developing hereditary diseases such as breast cancer. But researchers say they have now identified the first mutation associated with a higher risk of developing prostate cancer.

Researchers analyzed more than 200 genes from 94 men with prostate cancer along with their families. Men within four of the families were found to have a mutation of the gene protein known as HOXB13.

All 18 men within the four families who had prostate cancer also carried the HOXB13 gene mutation, according to the findings which were published Wednesday in the New England Journal of Medicine.

Researchers then compared gene results from nearly 7,000 European men, and found that those with prostate cancer had about 20 times the odds of carrying the mutation compared to men without prostate cancer.

"We found that the mutation was significantly more common in men with a family history and early diagnosis compared with med diagnosed later, after age 55, without a family," Dr. Kathleen Cooney, professor of internal medicine and urology at the University of Michigan Medical School and study author said in a public statement.

More than 2 million men are living with prostate cancer, according to the American Cancer Society. Cooney said only a small fraction of men might have this genetic mutation.

HOXB13 gene mutation has previously been linked to progressions in breast and ovarian cancer.  

Many experts say these new findings might turn into the equivalent of the BRCA gene mutation, which can identify a woman's genetic risk for breast cancer.

But until the findings are replicated in more men with various backgrounds, it's still too early to tell whether a simple blood test will be able to accurately tell a man's risk for the disease.

"At the moment this finding will not change screening, diagnosis or clinical knowledge of prostate cancer," said Janet Stanford, research professor and co-head of the program in prostate cancer research at the Fred Hutchinson Cancer Research Center. Stanford was not involved in the study.

Researchers still need to find whether men who have this mutation will go on to develop prostate cancer, Stanford said.