Unraveling the Prostate Genome

Extract

It used to be that scientists looking for the genetic roots of cancer could sequence only one DNA molecule at a time. Today, “massively parallel” techniques allow scientists to sequence billions of DNA molecules at once. That's led to a sharp drop in analytical costs and to the ability to sequence entire cancer genomes. In this new wave of genetic research, perhaps 100 cancer genome sequences are in various stages of completion. Scientists who study them will be able to see all the genetic variation in a given cancer cell—the whole spectrum of changes and rearrangements that might unleash tumor growth—not just simple spelling errors or deletions in DNA.

Last February, researchers from the Broad and Dana–Farber cancer institutes, in Boston, and Weill Cornell Medical College, in New York City, hit a milestone by publishing the entire prostate cancer genome in Nature . Whereas most published studies so far have presented just one cancer genome, these researchers sequenced seven, along with matched control genomes from noncancerous cells taken from the same patients. Each patient harbored tumors of at least T2 staging and Gleason grade 7 scores or higher.