Mutations in PALB2 Gene Increase Breast Cancer Risk in Old Women

A new study has found that women with mutations in PALB2 gene, on an average, have one in three chances of developing breast cancer by the age of 70 years.

Breast cancer is one of the most common types of cancer that U.S. women are diagnosed with. Despite its high prevalence, researchers aren't sure why normal cells become tumorous. According to most experts, breast cancer is caused by a combination of genetic, hormonal and environmental factors. Two genetic mutations - BRCA1 or BRCA2 - are commonly associated with increase in breast cancer risk.

The study was conducted by researchers at the University of Cambridge. For the study, the team analyzed data from 154 families without BRCA1 or BRCA2 mutations. This group included 362 people with PALB2 gene mutations.

The researchers found that women, who carried PALB2 gene mutation, had a 35 percent higher risk of developing breast cancer by the time they become 70 years old. The team maintains that a strong family history of breast cancer was associated with cancer risk in these women.

The proportion of women who carry this gene mutation is small, so researchers believe that additional studies are required to tease out the various factors that increase cancer risk in these women.

PALB2 was first linked with breast cancer in 2007 and is known to interact with both - BRCA1 and BRCA2.

The research was funded by the European Research Council, Cancer Research UK and multiple other international sources.

"Since the BRCA1 and BRCA2 mutations were discovered in the mid-90s, no other genes of similar importance have been found and the consensus in the scientific community if more exist we would have found them by now. PALB2 is a potential candidate to be 'BRCA3'. As mutations in this gene are uncommon, obtaining accurate risk figures is only possible through large international collaborations like this," said Dr Marc Tischkowitz from the Department of Medical Genetics at the University of Cambridge, according to a news release.

The study is published in the journal New England Journal of Medicine.