health media: BRCA1 Breast Cancer Risk Linked To Other Genes

"...People who carry certain mutations of the BRCA1 gene are known to have a higher risk of developing breast cancer.

Couch told the media that their findings should be "useful in helping determine individual risk for breast cancer in BRCA1 carriers".

"It also provides insights into hormone-receptor-negative breast cancer in the general population," he added.

For the study, Couch and colleagues conducted four phases of genome-wide association studies (GWAS) that altogether involved 20 research centers in 10 North American and European countries and Israel.

For the first phase, to identify candidate gene variants, they scanned the genomes of 1,193 carriers of BRCA1 mutations who were under 40 and had invasive breast cancer and compared them to scans of about the same number of controls: BRCA1 carriers of similar age who did not have breast cancer.

In comparing the genomes from the two populations the researchers examined over half a million genetic alterations. They found 96 pieces of DNA called SNPs, or "snips", short for single nucleotide polymorphisms, that they thought would be likely candidates because they differed between the two populations...."cont'd