All of us have some bad genes—variants for knock-knees, bad teeth, cardiovascular disease, diabetes.

Most of us don’t know what these variants are, and there’s probably not much to be done about most of them anyway. So we are spared the type of dilemma facing women who carry a timebomb—mutations in BRCA1 or BRCA2.

The choices are fairly stark for women with mutations in these genes—undergo surgery for a prophylactic mastectomy and ovary removal or face a high probability of breast and ovarian cancer.

Joanna Rudnick explores this dilemma in her documentary “In the Family” which airs tonight on PBS. She is also interviewed for today’s segment of “Talk of the Nation” on NPR.

I went to a preview of the film in Washington, DC this July—at en event also attended by local science celebrity Francis Collins (who also liked this film). Rudnick tested positive for a BRCA1 mutation at age 27 and turns the camera on herself, examining how women with the mutations weigh their choices. It’s a gut-wrenching and honest exploration.

Rudnick, who has not had children, decided to hold off on making a decision about surgery, but shows us women who made similar decisions, and came to regret them as cancer took hold. By portraying other women and their families—as they go with their sisters to get tested, and as they hold back the disease or succumb to it—she uses herself as a subject without being overbearing.

She also explores some of the political issues surrounding genetic testing, including an illuminating interview with Mark Skolnick, a proponent of gene patents, who proudly proclaims he ‘won’ the race to find the

BRCA1 gene after Mary Claire King showed the path to it. Skolnick went on to found Myriad Genetics, the company that has the rights to genetic testing of BRCA1 and BRCA2 in the US—a system with downsides, such as high pricing.

My only quibble with the film—and a lot of the press around this issue— is that it may dramatize the risk of the mutations, showcasing genetic counselors citing numbers as high as 90 percent for the risk of breast cancer in women with BRCA1 mutations. In reality, geneticists have argued about the degree of risk for years—with some studies showing risk closer to 50 percent or below.

I cannot imagine making life-changing decisions based on probabilities that even the experts can’t agree on. But whatever the exact numbers, as Rudnick shows, testing positive for a BRCA1 mutation changes life dramatically.