Sequencing a patient’s entire genetic code identifies treatments

Researchers at the Dartmouth Cancer Center have developed computer algorithms that help speed up the analysis of data produced by genetic sequencing — used when looking for mutations in a patient’s genetic makeup in order to deliver medical therapies that are specific to them.

“We have implemented a unique system that combines lab testing and data analysis in a timely fashion that will have a direct impact on patient care,” says Parth Shah, director of genomic informatics in the Center for Clinical Genomics and Advanced Technology (CGAT) at the Dartmouth Hitchcock Medical Center, who led the team that developed the data analysis process.

Thanks to the new algorithms, “whole exome sequencing” allows the laboratory to sequence all 20,000+ genes to get a complete look at a patient’s entire genetic code and to allow oncologists to pinpoint better treatments. However, this type of sequencing generates an enormous amount of data, making it incredibly challenging to analyze.

“Whole exome sequencing, when applied in a clinical setting, is a game changer for the entire Dartmouth Health system,” says Gregory J. Tsongalis, medical director of CGAT.

“To the best of our knowledge, the Dartmouth Cancer Center is the only cancer center in the country routinely doing clinical whole exome sequencing on solid tumors. Other centers are doing this on a research basis only. Sequencing is being run on specific tumor types at the moment, with the future goal of running it on all cancer patients.”

Tsongalis also notes that some insurance companies cover the service while others do not, but this is slowly changing.

While the main focus has been on cancer, the new test is also being applied to detecting variants of hereditary disease conditions. In addition, the data generated will allow researchers not only at Dartmouth Health but worldwide to probe the underlying mechanisms of disease to develop better diagnostic testing and therapeutics for patients.