This study created a detailed map of the different cell types in the human breast to understand how they change with age, pregnancy, and inherited cancer risks. Using advanced tools, researchers looked at thousands of individual cells and discovered new subtypes, including one called basal-luminal (BL) cells. These BL cells were unusual because they didn’t fit clearly into one category and increased with age—similar to patterns seen in more aggressive breast cancers. They also found that certain hormone-sensitive cells were less common in older women and those with BRCA2 mutations.
The Komen Tissue Bank played a key role by providing healthy breast tissue from a diverse group of women. These samples helped confirm that changes in specific cell types, like the rise in BL cells, happen naturally with age. This breast cell atlas gives scientists a better way to study how breast cancer might develop from normal cells and how risk factors like age and genetics affect the breast over time.
