Data Stretching Back to 1959 May Explain Link Between Environment and Breast Cancer
The lives of mothers, daughters and granddaughters in the Bay Area may offer clues to the link between chemical exposure and disease
While billions of research dollars have been spent on screening, treating and trying to cure breast cancer, still relatively little is known about its causes.Image: Flickr/TipsTimes
When Ida Washington received a letter inviting her to participate in a women’s health study to explore the environmental roots of breast cancer, she didn’t think twice. Her mother was diagnosed with the disease nearly 40 years ago, and since then, it has been a terrifying mystery she has yearned to unravel.
Washington was just a teenager when the lump was found on her mother’s left breast. In the years that followed, as her mother’s cancer went into remission, she began to wonder what caused it. “My mother didn’t smoke, she didn’t drink. Breast cancer didn’t run in the family,” she said. [Emphasis added]
Ida’s mother, Willie Mae Washington, now 92, participated in the first generation of a scientific study that has endured for more than half a century to investigate whether environmental exposures may trigger breast cancer. Now Ida Washington, 52, is continuing the legacy as part of its second generation.
The two women are among the more than 15,000 mothers, daughters and granddaughters in the San Francisco Bay Area enrolled in a project known as theChild Health and Development Studies, launched in 1959. Tens of thousands of samples of the women’s blood are stored, providing more than 50 years of continuous data on health outcomes and environmental exposures.
Scientists tap into this unique trove as they struggle to figure out what role environmental exposures play in the development of diseases such as breast cancer.
“These women are a national treasure,” said Barbara Cohn, director of the Child Health and Development Studies and Three Generations follow-up study, based in Berkeley, Calif. “They hold the key to understanding the risks.”
While billions of research dollars have been spent on screening, treating and trying to cure breast cancer, still relatively little is known about its causes. One in every eightwomen today will contract the disease during her lifetime. Genes account for only a small number of cases, 5 to 10 percent. Known risk factors include age, obesity and low physical activity. [Emphasis added]
Washington, her mother, and other members of the Bay Area study are uniquely poised to help researchers answer the why’s of breast cancer and other diseases afflicting women.
Over the years, this group of women and their children – known in scientific jargon as a cohort – has helped scientists understand how diseases can start even before birth and may pass from one generation to the next – not just through genes, but also by things in their environment.
Funded largely by the National Institutes of Health, hundreds of scientific studies have been published about these women since the 1960s.
One of the more groundbreaking findings provided a clue that smoking during pregnancy could harm the fetus. Also, based on these women, scientists discovered that exposure to the now-banned pesticide DDT during a mother’s pregnancy could decrease a daughter’s ability to become pregnant and increase a son’s risk of testicular cancer. New findings are expected to be published soon. [Emphasis added]
There are no research cohorts like it in the country. In fact, it may be the only one of its kind in the entire world.
The study group is “extremely valuable, almost unique,” said Shanna Swan, an environmental health scientist at Mount Sinai School of Medicine in New York who is not involved with the California research.