In 1994, discovery of the breast cancer 1 (BRCA1) gene fueled media reports of a single cause behind a single disease. Since then, a far more complex story has emerged, with evidence for both single genes contributing great effects, and many genes with small but additive effects. Many molecular roads, scientists now know, lead to breast cancer.
Only 5% of breast cancers are the consequence of germline mutations in a single gene. More commonly, cancers arise as somatic mutations, and many of these are probably polygenic in origin. "The risk of cancer is probably influenced by many unknown genes, with individual effects that are much smaller than the impact of BRCA1 or BRCA2; their collective contribution is large," says Colin Begg, the head of epidemiology and biostatistics at Memorial Sloan-Kettering Cancer Center in New York.
"SHOW ME THE PROTEINS" The new view of breast cancer genesis has its roots in ...