Dear all,

First of all, congrats to Marco: he's the *One and only* for that kind of work! We are lucky to have him as scientific coordinator.

About the VPH definition he is proposing. It is for sure well written and well-tuned, and I have no problem accepting it.

But (I will play here the Devil's lawyer) this discussion starts because VPH must show some differences with the Physiome (for various reasons, see previous discussion).

If I'm dissecting (sorry, I'm anatomist) Marco's new definition in pieces, I do not see how some of these pieces differ from what you could find in the Physiome concept (at least what I understood from it).

For example: "The term **Virtual Physiological Human** (VPH) indicates a shared resource formed by a federation of disparate but integrated computer models of the mechanical, physical, and biochemical functions of living human body in both physiological and pathological conditions."

It seems to me that the IUPS PHysiome Project website is already organised as a shared ressource. Quite empty at the moment, but the frame is there.

Other section: "VPH models are implemented as computer models and services, designed following community standards that make possible to exchange information and to realise a developmental process based on the federation of the various partial representations into what should become one day an exhaustive and complete representation of functions of the human body."

I do not think the Physiome mentions "services", but certainly "standards to realize developmental process" (see the so-called "markup language standards" on the above website and in the paper from Crampin, Hunter et al. (2004, Exp Physiol); also the idea of ontology requirement). The "exhaustive representation" is also present in most papers related to the Physiome.

Now, these similarities does not bother me a lot because Marco puts the accent clearly on technologies ("To create the VPH we need brand new technologies"), while Physiome doesn't. Note this technological definitions sounds close to the US Simbios (but we do not care I suppose).

I just wanted to point out there are still similarities. I add directly that such similarities are unavoidable and I think it is silly to try to hide the Physiome as a source of inspiration for some points. Also Marco seems to me to successfully define an original VHP "ideology" and give the project its own soul. So, I adopt it !

I just have a last comment: I'm not sure I like the idea of "exhaustive representation". Yes, sure as scientist it's an exciting challenge. But I'm pretty sure that neither the Clinics nor the Industry is waiting for such representation. Clinics is requesting tools to answer particular questions limited to some scales and levels (for example, cellular, tissue and organ levels, but not genetic). The Industry will probably follow what the Clinics is requesting. This is a discussion we have right now at ULB with clinicians working with cerebral palsy patients ... they clearly answered me after I explained the Physiome concept: "sure we are interested in new diagnostic tools, but focus first on the levels of interest, not the ones (i.e., genes) where there is no litterature in our field".

Now, of course this "exhaustive" idea is very sexy and probably very attractive to politicians and "their" citizens.

Serge