We all experience life in three-dimensional space. Right now, apparently solid computer keyboard keys “click” as they recoil from the press of my fingers, while a chair beneath my rear resists the gravitational pull of our planet to keep me at the right height to reach the keyboard and eye the screen. The keyboard, the screen and my body are defined in relation to each other by height, weight and depth. Indeed, everything we do at the organismal level – and everything going on in us at the submicroscopic level of atoms and molecules – can be imagined as spacial interactions in three dimensions.
But position in space incompletely describes life. We also exist in time, a phantasmagoric fourth dimension that we limited human creatures experience as part hope (the future), part memories (the past) and even part loss (the present, where the future blinks into life and is relegated to the past in the same blink). Physicists argue endlessly over whether the fourth dimension of existence is best described as a kind of flow, a spotlight, or even a “block universe” (where all past and present and future are always existing). Fascinating, brain-beating arguments that ultimately raise as many questions as they answer. Yet the basic idea of four-dimensionality is compelling.
As a central attribute of life, health is also a matter of space and time. At any given moment of time (the present) our state of health is determined by a combination of microscopic and macroscopic interactions. From the temperature in the room to the proteins quivering in each neural synapse, there is an unimaginably large set of interactions of “stuff” defining the present moment. And which will change in the “next” moment, the next, and so forth, until the end of our life. Each of us experiences the summation of these changes as our uniquely personal health history in three dimensions over the fourth dimension of time.
The reality of a fourth dimension is underlined by the third pillar of precision medicine, i.e., finding the right treatment for the right patient AT THE RIGHT TIME. However, most precision medicine today focuses on understanding the genome, the blueprint — but not an actual building block — of the human body. Proponents for a genomic approach to precision medicine argue that if we could only understand each two-dimensional representation of genetic variation in a person’s genome, we could foretell future illness accurately and would be ready to “fix” it when it became the present.
This assertion is akin to saying that one can look at a blueprint of a building constructed, say, 40 years ago and be able to pick out today where the pipes are leaking, the walls are sagging, and the foundation crumbling. A sharp-eyed builder who knew the materials used to build the blueprint’s depiction might be able to raise alarm about the potential future failure of various elements, but it would simply be impossible to be more precise without a different kind of insight.
So why not examine the building blocks of health directly? Specifically, why not measure the molecules of four-dimensional life? I am referring to proteins, which change regularly in response to environment (including drug treatment) and genetic alterations. Proteins interact with each other in time and space to build – and destroy – bodily life. And proteins reveal not only your immediate health status but where you are headed in the near future, far more accurately and precisely than genes.