Women play many important roles throughout their lives—daughter, mother, and friend—but no relationship is as unique as the one between two sisters. Sister Study researchers hope the sisters of women with breast cancer can play another important role by helping discover how our environment and genes affect our chances of developing breast cancer.

The Sister Study is a nationwide effort, conducted by the National Institute of Environmental Health Sciences, to learn about environmental and genetic causes of breast cancer. Women ages 35 to 74 are eligible to join if their sister (living or deceased), related to them by blood, had breast cancer; they have never had breast cancer themselves; and they live in the United States or Puerto Rico.

The Sister Study is particularly committed to enrolling women in every state, and from all backgrounds, occupations, races and ethnicities, so the study results represent and benefit all women. The women enrolled in the Sister Study look like many of our relatives, friends, and co-workers. They may even look like you.

Of the more than 33,000 women currently enrolled, here are a few who are making a difference in breast cancer research. Retiree Cruz Mireles, 58, joined because her sister is a breast cancer survivor. Jean Peelen, 65, a government retiree and senior model enrolled and helps spread the word about the Sister Study because one sister is a breast cancer survivor and another died as a result of the disease. Also, Donna Castleberry, 46, who works in a busy Los Angeles advertising firm, and Barbara Moore, 57, an on-the-go Labor Relations Specialist for AFSCME did it because their sisters died of breast cancer, before they even reached the age of 50.

The study needs to enroll 50,000 women by the end of 2007, and with your help, it can.

“Many women have heard about the Sister Study, but they haven't signed up yet, and we really need them now,” said Dale Sandler, Ph.D., Chief of the Epidemiology Branch at NIEHS and Principal Investigator of the Sister Study. “Doctors know very little about how the environment may affect breast cancer, that is why the Sister Study is so important. We hope women will make that call today,” she added

Organizations in partnership with the Sister Study include the American Cancer Society, the Intercultural Cancer Council, the National Center on Minority Health and Health Disparities of the National Institutes of Health, Sisters Network Inc., Susan G. Komen for the Cure,  and Y-ME National Breast Cancer Organization.

The Sister Study is available in English and Spanish and can be done from home when it is convenient for women. To learn more about the Sister Study, visit the web site www.sisterstudy.org, or for Spanish www.estudiodehermanas.org.  A toll free number is also available 1-877-4SISTER (877-474-7837). Deaf/Hard of Hearing call 1-866-TTY-4SIS (866-889-4747).

Woman by woman….Sister by sister…We can make a difference.