title: The molecular and mathematical basis of Waddington's epigenetic landscape: a framework for post-Darwinian biology?
abstract: The Neo-Darwinian concept of natural selection is plausible when one assumes a straightforward causation of phenotype by genotype. However, such simple 1:1 mapping must now give place to the modern concepts of gene regulatory networks and gene expression noise. Both can, in the absence of genetic mutations, jointly generate a diversity of inheritable randomly occupied phenotypic states that could also serve as a substrate for natural selection. This form of epigenetic dynamics challenges Neo-Darwinism. It needs to incorporate the non-linear, stochastic dynamics of gene networks. A first step is to consider the mathematical correspondence between gene regulatory networks and Waddington's metaphoric 'epigenetic landscape', which actually represents the quasi-potential function of global network dynamics. It explains the coexistence of multiple stable phenotypes within one genotype. The landscape's topography with its attractors is shaped by evolution through mutational re-wiring of regulatory interactions - offering a link between genetic mutation and sudden, broad evolutionary changes.
authors.affiliation: Institute for Systems Biology, Seattle, WA, USA. sui.huang@systemsbiology.org
authors.forename: Sui
authors.initials: S
authors.lastname: Huang
mesh_terms: D000818:Animals; D005075:Biological Evolution; D044127:Epigenesis, Genetic; D005786:Gene Expression Regulation; D053263:Gene Regulatory Networks / Q000502:physiology*; D005838:Genotype; D006801:Humans; D008957:Models, Genetic; D010641:Phenotype; D012641:Selection, Genetic