Scientists in St. Louis have decoded the entire genome of a woman who died of leukemia and in the process, they identified several mutations that probably caused the disease, accelerated its progression or rendered it resistant to chemotherapeutic agents.
The researchers sequenced DNA from the woman’s leukemia cells and her non-cancerous skin cells, and then compared them side-by-side. The comparison revealed 10 mutations that were present only in the cancer cells.
“This is the first of many of these whole cancer genomes to be sequenced,” Richard K. Wilson told the New York Times. Wilson is Director of the Genome Sequencing Center at Washington University and a senior author on the paper published in Nature. “They’ll give us a whole bunch of clues about what’s going on in the DNA when cancer starts to bloom,” he added.
The scientists’ strategy to sequence the entire genome of a human cancer cell represents a break from previous approaches that had focused on a few hundred “likely suspect” genes. The strategy has been enabled by recent advances that make it far cheaper and quicker to sequence large amounts of DNA. The advantage of the new strategy is that it eliminates the possibility that the genes actually associated with cancer are not among the “likely suspects.”
Indeed Wilson’s group found that 8 of the 10 mutations in their study were not considered likely suspect genes.
The woman’s sequenced DNA will be made available for other research projects. Before her donation, the only fully sequenced human genomes had come from Craig Venter, the founder of the Institute for Genomic Research, and Nobel Prize winning molecular biologist James Watson.