Biology Reference
In-Depth Information
possible to decode the genetic programmes that are supposed to
control embryonic development by reading these genomes. There
are far fewer genes than seem necessary to explain all the functions
performed by an organism. As a result of these limits to genetic
determinism, we are now seeing a real change of paradigm, with the
emergence of systems biology.
Instead of focusing our understanding of organisms on their
DNA, we are trying to see and understand them as systems. We are
seeking, in this new context, to find the balance between the influ-
ences arising from the various levels, which include the DNA, the
networks of proteins, the cell tissues, the organism and the envi-
ronment. This post-genomic biology requires enormous use of bio-
computing to integrate the huge quantities of data collected by
large-scale transcriptome and proteome analysis. The aim of these
programmes is to identify all the RNAs and proteins in a cell in
order to establish a map of the interactions they have with each
other in the form of networks. It is thus hoped to arrive at a
complete description of how a cell functions. However, scientific
progress does not result simply from accumulating data. The obser-
vations made depend just as much on the theories which guide the
research as on the reverse. Systems biology will not succeed in going
beyond the contradictions of evolutionary synthesis unless it also
resolves the original problem concerning separating evolution from
embryogenesis. To do this, a new conceptual framework needs to be
developed.
Ontophylogenesis (or cellular Darwinism) resolves this problem
and provides a conceptual context in which DNA is not omnipo-
tent. It breaks with traditional theories by considering embryonic
development and evolution as a single process. It consists of apply-
ing Darwinism to the interior of organisms, no longer just to the
DNA but also to how a cell functions as well. It thus leads to a gen-
eral conception in which the question of biological individuation can
be tackled from a new angle. It is this theory which is the subject
of this topic, in the course of which various extensions of it will
gradually be discussed.
