The ability to sequence and screen the entire genetic information of an individual is now within reach. DNA sequencing costs have decreased over a 100-fold over the past 3 years, a rate faster than Moore’s law on computer power increases with time would predict.
Sally in her post on Pharma Strategy Blog discusses the two JAMA papers that look at whole genome sequencing in cancer patients. The first paper by Link and colleagues from Washington University, St Jude Children’s Research Hospital and University of Chicago is a sad case of a woman diagnosed with breast cancer at 37, ovarian cancer at 39 who died of treatment related AML (tAML) aged 42. Whole genome sequencing showed that she had a novel deletion of 3 exons of the TP53 gene. Screening her children for this deletion will help identify potential future risk.
In the second paper, Welch and colleagues at Washington University report on the whole genome sequencing of a 39 year old woman initially diagnosed with AML, and how this led to discovery of a novel insertional translocation on chromosome 17 that produced a pathogenic PML-RARA gene fusion. Once this was discovered after sequencing, the patient’s diagnosis and treatment was changed to incorporate this knowledge, with an improved prognosis; she remains in remission according to the paper.
The cost of whole genome sequencing is still too high for it to be part of routine screening for everyone, but the time will come in the not too distant future when this is cost effective, opening up a new era of personalized medicine.
Sally Church has published an in-depth analysis of whole genome sequencing and a review of the JAMA papers on Pharma Strategy Blog that is well worth reading.