Abstract
Minimal genetic pre-formationism is defended, in that primacy is ascribed to DNA in the structuring of molecules through molecular codes. This together with the importance of such codes for stability and variation in living systems makes DNA categorically different from other causal factors. It is argued that post-transcriptional and post-translational processing in protein synthesis does not rob DNA of this structuring role. Notions of structuring causal powers that may vary in degree, of arbitrary molecular codes that are more or less realized, of partial templating and of genetic information as a subspecies of mechanistic information are brought in to support this and to rival causal and semantic notions of information. It is concluded that the primacy of genes in their structuring of molecules goes together with parity between genes and non-genetic causal factors in regulation of living systems. This is seen to hold independently of the radical reconceptualization of organism cum environment that has been suggested in developmental systems theory