Four Genes Newly Linked to Breast Cancer

Four previously-unsuspected genes appear to play a significant role in the development of breast cancer.

Scientists compared the genomes of 4,400 women with breast cancer to those of 4,300 women without. After identifying 30 suspicious differences in DNA, they then searched for these differences in over 20,000 women with breast cancer and an equally large control group.

Of the four genetic variations that emerged, three involve genes that regulate the growth of cells. The researchers say their discovery will have more impact on our understanding of breast cancer than on predictive tests.

At present, scanning these newly discovered genes would tell us little about a woman's cancer risk. But as more and more genetic risk factors are uncovered, genetic profiling could give doctors a fine-grained picture of individual risk, and could even lead to bespoke treatments offering the best chance of preventing or treating the disease.

"As more genes are identified, tests will become more predictive," says
Easton. "I wouldn't be at all surprised if there were dozens or hundred of genes involved." A similar approach ought to work for other diseases
— Easton is now studying prostate cancer.

But it seems to me that the predictive value is actually being underplayed a bit here: women with two copies of a variation in one of the genes, called FGFR2, have a 60% greater chance of developing breast cancer -- and approximately 16% of women have these variations.

If the faulty FGFR2 is found in tandem with mutations in BRCA1 and
BRCA2 genes -- the current targets of breast cancer gene tests -- heightened care and more-than-regular mammograms would seem to be justified.

Related Wired coverage here.

Geneticists identify four new breast-cancer genes [Nature]
*
Image: Gare and Kitty*