A common consequence of the evolutionary process in many species is extensive genetic diversity. As has become apparent in recent studies (Tennessen et al., Science 2012; Nelson et al., Science 2012), the growth of the human population coupled with what is believed to be reduced selective pressure, presumably in part due to the life-promoting and life-saving effects of modern medical interventions, has facilitated a truly impressive range of rare variants in human genomes. Some of these rare variants are expected to be associated with predispositions to various diseases and medical conditions. Hence, as a consequence of human evolution the need for personalized medicine arises.
It is in this context that a recent study (Chen et al. Cell 2012) by Michael Snyder, the chairman of the Stanford Genetics Department, and his colleagues is of special interest. It is a technological tour de force and tour de self applied to blood samples from Snyder himself and in which Snyder and his associates combine multiple systematic high-throughput types of analysis (genomics, transcriptomics, proteomics, metabolomics, and more) i.e., as the authors’ preferred jargon would have it, a multi-dimensional integrated personal omics profile (iPOP). This analysis revealed a genetic variant predisposing to type 2 diabetes mellitus that led Snyder to screen for type 2 diabetes which subsequently developed. The authors claim that therefore this approach is a guide to the personalized medicine of the future. In what follows, I evaluate these claims, informed in part by my personal experience with an infrequently-recognized form of personalized medicine that has been in operation for no less than 15 or so years and possibly much longer depending on how precisely the concept is defined. I emphasize at the start that I support a role for personalized medical care in several senses not limited to the purely genetic but note that this approach, the substantial hype notwithstanding, nevertheless faces challenges and limitations. (more…)
