Return to Principles of Development 6e Student Resources

Chapter 12 Web links and web activities

Growth, post-embryonic development and regeneration

Cancer can result from mutations in genes that control cell multiplication and differentiation 
The Wnt genes are essential for embryonic development, helping orchestrate everything from the differentiation of the head and tail ends to the formation of kidney tubules, and faulty Wnt genes can also spur cancer (page 564 Wolpert text). Visit Roel Nusse’s “Wnt Homepage” ( website at Stanford University and follow the “Mouse Wnt Genes” and “Wnt Signaling in Human Disease” and the Image: “Wnt in Cancer” links to learn more about the mutations in Wnt genes that lead to a variety of diseases.

Genes controlling regeneration in Hydra are similar to those expressed in animal embryos.

The Wnt pathway that leads to activation of b-catenin (see section 4.2 on page 148 in Wolpert text) is essential for Hydra development (Box 12C pages 582-583 in Wolpert). Visit Roel Nusse’s “Wnt Homepage” at Stanford University ( to keep tabs on this growing gene family through the genomic databases of different organisms. In particular, check out the following links:

  • Learn more about the role of Wnts in the formation of very diverse body plans through links to “Evolutionary Origin Wnt Components”.
  • At the bottom of the Wnt Homepage click on the diagram “Comparison of Wnt-Hedgehog” and list the features that these two pathways have in common.