BOB ABERNETHY, anchor: As a result of the Human Genome Project, we are now able to locate genetic mutations and know much more about a person's medical future than ever before. And this new knowledge has given rise to many medical, legal, and ethical questions. Betty Rollin has our report.

BETTY ROLLIN: Marcy Golub is not having an ordinary blood test. She's being screened for BRCA 1 and 2 -- genetic mutations that frequently lead to breast and ovarian cancer.

MARCY GOLUB: My sister was diagnosed with breast cancer in 1982; after that she was diagnosed with ovarian cancer in 1994. At the suggestion of my doctor, I went through the cancer risk evaluation program.

ROLLIN: As a result of her family history, Marcy is at risk for having the mutation, especially since her sister tested positive for BRCA 1. Before her blood was drawn, Marcy, like all patients planning to undergo genetic testing, was encouraged to meet with a counselor.

MS. JILL STOPFER (Genetic Counselor, University of Pennsylvania Cancer Center): What I try to do with everyone is to help them make their own best decision about what's right for them. To make sure that someone understands the risks and benefits and limitations of testing; to make sure when the results are available, the results are understood.

ROLLIN: Some patients may not want to deal with the results if they're bad.

MS. STOPFER: If someone is expressing feelings of concern about testing to the point where they are really not sure, I'll encourage them to follow their feelings about what to do.

ROLLIN: In Marcy's case, a positive finding for BRCA 1, the mutation she's most likely to have, would mean that her chances of getting breast cancer are more than 50%, and of ovarian cancer, 20 to 40%. Ovarian cancer is her greater concern since it's harder to detect.

MS. STOPFER: If she's positive, we will recommend strongly that she have her ovaries removed.

MS. GOLUB: I feel that if I have this prophylactic surgery, I'm one step ahead of the game if I have a mutation. If I don't, I can breathe easy.

MS. STOPFER: We caution people that everyone has some risk for developing cancer. This doesn't make you risk free, but the level of risk is certainly very, very different.

ROLLIN: There are some nonmedical risks as well. The release of genetic information may cause people to lose their insurance -- even their jobs.

Representative Louise Slaughter (D-NY, at House Energy and Commerce Committee Hearing, July 11, 2001): Today's hearing proposes to address the potential for genetic discrimination. Unfortunately, genetic discrimination is not just a theoretical possibility; it's a reality.

JUDITH BENKENDORF(genetic counselor and policy consultant): People are so afraid of discrimination based on genetic information that is learned from tests that they are not getting tests and they are also not participating in research protocols.

ROLLIN: As of now, laws dealing with genetic discrimination vary from state to state. Federal law protects only those who have group insurance policies. Bills in the House and Senate that would provide more extensive coverage are pending.

There are privacy issues within families as well.

MS. BENKENDORF: There is a tremendous tension in family members between the right to privacy if you have a genetic test and you don't want anybody else to know versus the responsibility to share that information with other family members.

ROLLIN: Within families, there also may be other questions and conflicts: whether to test one's children -- whether to have children, even whether to marry.

For example, Orthodox (and Hasidic) rabbis created Dor Yeshorum, a program to test for Tay-Sachs and other diseases, which particularly threaten the Jewish community. Since Orthodox Jews are against abortion, they screen adolescents, with the hope of preventing marriages between two carriers.