The elucidation of the human genome sequence has made it possible to identify genetic alterations in cancers in unprecedented detail.
Dr Tobias Sjöblom and colleagues from Baltimore determined the sequence of well-annotated human protein-coding genes in 2 common tumor types.
The team analyzed 13,023 genes in 11 breast and 11 colorectal cancers, and found that individual tumors accumulate an average of 90 mutant genes.
|An average of 11 genes per tumor were mutated at significant frequency|
However, only a subset of these contribute to the neoplastic process.
Using stringent criteria to delineate this subset, the researchers identified 189 genes, an average of 11 per tumor, that were mutated at significant frequency.
The vast majority of these genes were not known to be genetically altered in tumors.
The team predict that these genes affect a wide range of cellular functions, including transcription, adhesion, and invasion.
Dr Sjöblom's team concludes, “These data define the genetic landscape of 2 human cancer types, provide new targets for diagnostic and therapeutic intervention, and open fertile avenues for basic research in tumor biology.”