Women who have had a sister with breast cancer can make a difference in the fight against the disease by joining the Sister Study, an important nationwide effort to find the causes of breast cancer.

In Minnesota, more than 3,200 women will be diagnosed with breast cancer and approximately 600 will die from the disease. Breast cancer is the most commonly diagnosed cancer among Minnesota women except for non-melanoma skin cancer.

Nationwide, the Sister Study is looking for 50,000 women ages 35-74, who have not had breast cancer themselves and who come from all walks of life. A major challenge in studying breast cancer and the environment has been the lack of useful data gathered before diagnosis about exposures and lifestyle factors.

Because of shared genes and lifestyle, sisters of women with breast cancer have an increased risk of developing the disease themselves. By studying sisters, researchers hope to identify risk factors that may help find ways to prevent breast cancer.

"This might be the greatest gift a woman could give to her sister this year," American Cancer Society Minnesota Health Promotions Manager Freda Carlson said. "Our hope is that awareness of this program will lead to action so that we can all learn more about the causes of breast cancer."

For more information about how to join the study, contact the American Cancer Society at 1-800-227-2345 or online at www.cancer.org.