CardioExchange Archive

Genomics Rubber Meets the Clinical Road: In a study without precedent, an asymptomatic 40-year-old man with a family history of coronary disease and sudden death received a comprehensive analysis of his full genome. According to the report in the Lancet, the investigators from Stanford and Massachusetts General Hospital found evidence that the man was at increased risk for MI, type-2 diabetes, and some cancers. He also had several rare variants of genes associated with sudden cardiac death, as well as variants associated with a good response to statins and resistance to clopidogrel. The results, write the authors, “provide proof of principle that clinically meaningful information can be derived about disease risk and response to drugs in patients with whole genome sequence data.”
   In an accompanying comment, Nilesh Samani, Maciej Tomaszewski, and Heribert Schunkert write that “even if the direct cost of sequencing whole-individual genomes becomes affordable, there are many practical challenges that will need to be overcome if the personal genome is going to enter clinical practice. Arguably of greater importance are ethical issues: who should have their genome sequenced, what counseling should be provided before and after testing and by whom, and who should have access to an individual’s genetic information. Whereas these issues are familiar in genetic testing, the scale of the data contained within each personal genome, and the potential implication for so many different aspects of an individual’s health (and the health of their relatives), mean that these issues will need to be even more carefully considered (and legislated on where necessary) to prevent misuse.”
  
The Lancet also published a Viewpoint, in which several of the authors of the original paper note that the clinical relevance of most of the data in genomic studies is unclear, and even when there is a clear message there may be no therapeutic options. They also note the potential strain on the healthcare system of simply conveying the results to people: “We predict that an average person might need information about roughly 100 genetic risks discovered in their genome. Even if that information averaged only 3 min per disorder, this process would take more than 5 h of direct patient contact, after many hours of background research into the importance of the various genomic findings.”