When we think of GIS, we think of geography in terms of Earth's surfaces. Whether we are looking at a world map or a map of the county, there is still a basic and common geography that we all have as a baseline.
What about the human body? We could certainly learn a lot about the body's systems by plotting points of data onto a map of the body. The most difficult part is that there are an infinite number of body shapes in the world, so implementing a GIS of the body must either be quite generic or patient specific.
There are a lot of places this type of GIS could go, and some are already exploring it. At the National Library of Medicine, the Visible Human Project has been in the works for about two decades. The data set for the Visible Human Project consists of MRI, CT and anatomical images. The University of Colorado has created the Functional Atlas of the Visible Human, which includes several teaching modules.
The CAVEman Human Body Project is a newer, perhaps less accessible project at the University of Calgary. From the website:
The CAVEman Project aims to create visual maps of information about diseases that have a genetic component, such as cancer, diabetes, and Alzheimer's. Using an immersive virtual reality environment called the CAVE, the research team will integrate a high-resolution digital atlas of a human body with medical data related to specific diseases. The final result will be a next-generation 4D (space and time) visual system to "see" disease processes and the effects of interventions, such as drugs, on these processes.
It will be interesting where this branch of GIS will go. Anders Sandberg has
blogged about this topic, which is worth a look.