Excess estrogen levels during pregnancy can disable, in their daughters, a powerful breast cancer tumor suppressor gene, say researchers at Georgetown Lombardi Comprehensive Cancer Center. They found the DNA repair gene BRCA1 to be silenced in one year-old girls exposed to a high hormonal fetal environment. The researchers say their study, presented at the AACR Annual Meeting 2013, suggests that BRCA1 silencing by methylation in utero may be an important mechanism that increases breast cancer risk later in life. And they say that, if confirmed, there could be ways of lowering that risk before breast cancer develops.
