Although I might quibble with the exact numbers in the piece, the big picture is this: BRCA1 increases the risk of developing breast cancer about five fold and increases the risk of ovarian cancer more than 10 fold.

CNN: What Angelina Jolie forgot to mention

Although I might quibble with the exact numbers in the piece, the big picture is this: the mutation increases the risk of developing breast cancer about five fold and increases the risk of ovarian cancer more than 10 fold.

CNN: What Angelina Jolie forgot to mention

And the more recently discovered breast density is the strongest with roughly a 4-fold increase in risk.

FORBES: After 40 Years Of Research, What Do We Know About Preventing Breast Cancer?