The opportunity for canalization and the evolution of genetic networks

[Guest guest]

Medical News Today 03 Feb 2005

The opportunity for canalization and the evolution of genetic networks

The recent explosion of genomic data has inspired a renewed interest in how

groups of genes work together to create observable phenotypes. Studies of

genetic networks have shown a surprising degree of robustness to variation,

regardless of whether the variation comes from a change within or outside of the

network.

One explanation for this pattern is that evolution has acted to create genetic

networks that are robust to mutational defects at single genes within the

network. Using a combination of mathematical and computational models,

R. Proulx and C. investigate the evolution of genetic networks

in response to a variety of genetic and environmental perturbations.

The models show that natural selection for robustness will only be as strong as

the cost of disrupting the network. Because the risk of mutational damage is

limited by the mutation rate, these results imply that robustness to mutation

will play only a small part in the evolution of genetic networks.

Environmental perturbations, on the other hand, can affect large fractions of a

population and are thus more likely to play a significant role in genetic

network evolution.

This article will appear in the February 2005 issue of American Naturalist.