We’ve known for many years that women who have mutations in the BRCA genes are at an increased risk for developing breast cancer – up to five times higher than women who don’t carry the mutation. Researchers have been working hard to understand just why the mutations are linked to breast cancer development, and now they’ve found an important clue.

Though more research needs to be done to understand the complete cascade of events, this is an exciting step in unraveling the BRCA mystery.

“Since BRCA1 was first discovered in 1994, a major emphasis in hereditary breast cancer research has been to elucidate how BRCA1 mutations cause cancer,” said lead researcher Thomas Ludwig. So strong is the connection, some women who carry the BRCA mutations opt to have preventative mastectomies. And because the genes are also linked to other types of cancer, such as ovarian cancer, researchers are especially eager to figure out the chain of events involved in the BRCA-cancer relationship.

Ludwig and his team began their investigation with a suggestion from previous research that the culprit in BRCA is a region of the gene that codes for an enzyme. So they created a strain of mice with mutations on the BRCA gene that cause it to lose its enzymatic function. But they observed that these mice did not develop tumors any more than normal mice did.

So the researchers turned their attention on other areas of the gene. They found that when an area involved with recognizing certain phosphoproteins (like Abraxas, Bach1, and CtIP) was faulty, the mice often developed tumors – more often than normal mice. They concluded that this area of the gene that was needed for recognizing the phosphoproteins was essential in the suppression of tumors.

Though more research needs to be done to understand the complete cascade of events, this is an exciting step in unraveling the BRCA mystery. The researchers will next try to figure out the full range of phosphoprotein interactions involved in the suppression of tumors. Doing so could mean promising new avenues of breast cancer treatment.

The research was carried out by a team at the Institute for Cancer Genetics at Columbia University, and published in the journal Science.