Int J Biol Sci 2006; 2(3):95-103. doi:10.7150/ijbs.2.95


Hox genes are not always Colinear

Ana Sara Monteiro, David E.K. Ferrier

Department of Zoology, University of Oxford, UK


The deuterostomes are the clade of animals for which we have the most detailed understanding of Hox cluster organisation. With the Hox cluster of amphioxus (Branchiostoma floridae) we have the best prototypical, least derived Hox cluster for the group, whilst the urochordates present us with some of the most highly derived and disintegrated clusters. Combined with the detailed mechanistic understanding of vertebrate Hox regulation, the deuterostomes provide much of the most useful data for understanding Hox cluster evolution. Considering both the prototypical and derived deuterostome Hox clusters leads us to hypothesize that Temporal Colinearity is the main constraining force on Hox cluster organisation, but until we have a much deeper understanding of the mechanistic basis for this phenomenon, and know how widespread across the Bilateria the mechanism(s) is/are, then we cannot know how the Hox cluster of the last common bilaterian operated and what have been the major evolutionary forces operating upon the Hox gene cluster.

Keywords: Amphioxus, echinoderm, hemichordate, deuterostomes, Temporal Colinearity.

This is an open access article distributed under the terms of the Creative Commons Attribution (CC BY-NC) License. See for full terms and conditions.
How to cite this article:
Monteiro AS, Ferrier DEK. Hox genes are not always Colinear. Int J Biol Sci 2006; 2(3):95-103. doi:10.7150/ijbs.2.95. Available from