Dynamic Development


Main Page Dynamic Development

The Foundations of Developmental Biology


From Sperm and Egg to Embryo

Genetic Regulation of Development

Organizing the Multicellular Embryo

Generating Cell Diversity

Dynamic Development at a Glance

Learning Resources

Research Resources

The Developmental Biology Journal Club

Developmental Biology Tutorial

Genome Constancy

Does the genome retain its integrity during development?

Today, we shall go to The University of Pittsburgh, where Dr. Richard Carthew will discuss genome equivalence and its consequences for development.

The text references in Dr. Carthew's module are to Gilbert (1997). Comparable material can be found in

  • Browder et al. (1991) on pages 395-425,
  • Kalthoff (1996) on pages 141-161,
  • Shostak (1991) on pages 479-488
  • Wolpert et al. (1998) on pages 269-281

Until recently, the evidence had been overwhelming that irreversible changes do occur in nuclei of adult animals that would preclude them from being reprogrammed to promote complete, normal development when implanted into an anucleate egg. However, Dolly has indicated that we may have been wrong. Mammalian cloning is now a reality. Use the mammalian cloning link to fulfil the following learning objectives:

  • How have our ideas of nuclear potency changed as the result of recent advances in transplanting mammalian nuclei?
  • Review the technique used for producing Dolly.
  • What are potential applications of mammalian nuclear transplantation?
  • Do you think there should be limits on cloning of mammals in general or humans in particular?

Additional Learning Objectives for This Module

  • Review the technique that Briggs and King used for nuclear transplantation in Rana pipiens.
  • Compare the results that Briggs and King obtained from transplanting nuclei from blastulae, gastrulae, neurulae and tadpoles into enucleated eggs.
  • Review the technique that Gurdon used for nuclear transplantation in Xenopus laevis.
  • Compare the results he obtained with those obtained by Briggs and King.
  • What do the results of Southern blotting experiments tell us about genome constancy during development?
  • What is the concept of differential gene expression?

Digging Deeper:

Chan, A.P. and Gurdon, J.B. 1996. Nuclear transplantation from stably transfected cultured cells of Xenopus. Int. J. Develop. Biol. 40: 441-451.


Browder, L.W., Erickson, C.A. and Jeffery, W.R. 1991. Developmental Biology. Third edition. Saunders College Pub. Philadelphia.

Gilbert, S.F. 1997. Developmental Biology. Fifth edition. Sinauer. Sunderland, MA.

Kalthoff, K. 1996. Analysis of Biological Development. McGraw-Hill. New York.

Shostak, S. 1991. Embryology. An Introduction to Developmental Biology. HarperCollins. New York.

Wolpert, L., Beddington, R., Brockes, J., Jessell, T., Lawrence, P. and Meyerowitz, E. 1998. Principles of Development. Current Biology. London.

Dynamic Development at a Glance
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Dynamic Development is a Virtual Embryo learning resource

This material may be reproduced for educational purposes only provided credit is given to the original source.
Leon Browder & Laurie Iten (Ed.) Dynamic Development
Last revised Thursday, June 25, 1998