Wagner's gene network model

Wagner's gene network model is a computational model of artificial gene networks, which explicitly modeled the developmental and evolutionary process of genetic regulatory networks. A population with multiple organisms can be created and evolved from generation to generation. It was first developed by Andreas Wagner in 1996 and has been investigated by other groups to study the evolution of gene networks, gene expression, robustness, plasticity and epistasis.

The model and its variants have a number of simplifying assumptions. Three of them are listing below.

The model represents individuals as networks of interacting transcriptional regulators. Each individual expresses ${\displaystyle n}$ genes encoding transcription factors. The product of each gene can regulate the expression level of itself and/or the other genes through cis-regulatory elements. The interactions among genes constitute a gene network that is represented by a ${\displaystyle N}$ × ${\displaystyle N}$ regulatory matrix ${\displaystyle (R)}$ in the model. The elements in matrix R represent the interaction strength. Positive values within the matrix represent the activation of the target gene, while negative ones represent repression. Matrix elements with value 0 indicate the absence of interactions between two genes.

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